Add demo/test corpus kit: one sample file per platform behavior

9 new corpora covering every warning code and ingest path (text QA,
language mismatch/uncertain/unsupported, truncation, multi-column
suggestion, semicolon + latin-1 + xlsx ingestion, MFQ-2 themed spread)
plus sample_data/README.md mapping each file to what it triggers.
All detection behavior verified against the real warnings_engine.

CHANGELOG.md

@@ -5,6 +5,11 @@ Format: [Keep a Changelog](https://keepachangelog.com/). User-visible changes on
 ## [Unreleased]
 
 ### Added
+- Demo/test corpus kit in sample_data/ (one file per behavior): all text-QA warnings,
+  French and mixed-language corpora for every language check, token-window truncation,
+  multi-column text suggestion, semicolon and latin-1 ingestion, XLSX upload, and an
+  MFQ-2-themed corpus showing per-foundation score spread. sample_data/README.md maps
+  each file to what it triggers.
 - Searchable construct picker replacing the flat dropdown: search by scale, construct, or
   category; results grouped by category; recently-used constructs pinned on top; full
   keyboard navigation. Scales to hundreds of library entries.

sample_data/README.md

@@ -0,0 +1,30 @@
+# Sample data: demo and test corpus kit
+
+One file per platform behavior. To demonstrate or manually test something, upload the
+file named for it and follow the "How to trigger" column. Unless stated otherwise,
+select language English and model MiniLM.
+
+| File | Demonstrates | How to trigger / what you see |
+|---|---|---|
+| `sample_corpus.csv` | Clean baseline run (60 rows) | Run any construct; no warnings expected |
+| `warnings_showcase.csv` | All text-QA warnings at once | Run as-is: EMPTY_ROWS_DROPPED (2), DUPLICATE_TEXTS (2), TEXT_TOO_SHORT (3), TEXTS_MAYBE_TRUNCATED (2). Language detects cleanly as English, so no false language alarms |
+| `french_demo.csv` | Language checks (24 French rows) | Select English: LANGUAGE_MISMATCH (detected fr at 100%). Select French + MiniLM: MODEL_LANGUAGE_UNSUPPORTED. Select French + Multilingual E5: no warning |
+| `demo_spanish.csv` | Same checks in Spanish + short rows | Select English: LANGUAGE_MISMATCH; includes "si"/"no" rows for TEXT_TOO_SHORT |
+| `mixed_language_demo.csv` | Uncertain detection (15 EN + 15 ES) | Majority is 50%, below the 70% threshold: LANGUAGE_UNCERTAIN, checks skipped rather than guessed |
+| `long_documents_demo.csv` | Token-window truncation | 4 of 10 texts exceed MiniLM's 256-token window: TEXTS_MAYBE_TRUNCATED. Results table shows snippet ellipsis on long texts |
+| `moral_foundations_demo.csv` | Meaningful score spread (42 rows, 6 themed per MFQ-2 foundation + 6 neutral) | Run each MFQ-2 foundation against the same corpus: top texts change per foundation, neutral rows sink to the bottom. Also the corpus-reuse story: same corpus, many constructs |
+| `multi_column_demo.csv` | Text-column suggestion | 5 columns (id, author, comment_text, created_at, upvotes); the app should suggest `comment_text` |
+| `semicolon_delimited_demo.csv` | Delimiter sniffing | Semicolon-separated, texts contain commas; parses into exactly id + text |
+| `latin1_encoding_demo.csv` | Encoding fallback | Not valid UTF-8; ENCODING_FALLBACK warning, accented words (fiancée, café) must render correctly |
+| `xlsx_upload_demo.xlsx` | Excel ingestion path | Uploads and parses like a CSV |
+| `large_demo.csv` | Anonymous upload caps (800 rows) | Signed out: blocked with the sign-in hint. Signed in: runs |
+
+Notes:
+
+- Files with fewer than 20 detectable rows (long_documents, multi_column, semicolon,
+  latin1, xlsx) also show an info-level LANGUAGE_UNCERTAIN notice. That is the
+  minimum-rows guard by design: the platform refuses to judge a corpus language from a
+  handful of rows instead of guessing.
+- Warnings are computed per run and stored in that run's results. To see different
+  warnings, start a new run with the relevant selection; old result pages do not update.
+- All texts are synthetic, written for this kit. No real participant data anywhere.

sample_data/french_demo.csv

@@ -0,0 +1,25 @@
+id,text
+1,"Je suis très satisfait de ma vie en ce moment, même si tout n'est pas parfait."
+2,Ma famille compte plus que tout pour moi et je ferais n'importe quoi pour elle.
+3,Le travail devient de plus en plus difficile mais mes collègues me soutiennent beaucoup.
+4,J'ai passé le week-end à la campagne avec mes amis et c'était merveilleux.
+5,"Il faut toujours aider les personnes qui souffrent, c'est notre devoir moral."
+6,La justice est la valeur la plus importante dans une société moderne.
+7,Je me sens un peu seul depuis que j'ai déménagé dans cette nouvelle ville.
+8,Les traditions de notre région se perdent et cela me rend vraiment triste.
+9,Mon médecin m'a conseillé de faire plus d'exercice et de mieux dormir.
+10,Nous devons respecter nos aînés et écouter leurs conseils avec attention.
+11,"Chaque personne mérite les mêmes chances, peu importe son origine sociale."
+12,J'ai enfin trouvé un équilibre entre ma vie professionnelle et ma vie personnelle.
+13,La lecture du soir est devenue mon moment préféré de toute la journée.
+14,Mes enfants grandissent si vite que chaque moment passé ensemble est précieux.
+15,Je trouve que la solidarité entre voisins a beaucoup diminué ces dernières années.
+16,"Après des années difficiles, je commence enfin à me sentir en paix."
+17,Le respect des règles communes rend la vie en société possible et agréable.
+18,J'économise depuis deux ans pour réaliser mon rêve de voyager en Asie.
+19,La musique m'aide énormément quand je traverse des périodes de stress.
+20,Il est important de dire la vérité même quand cela nous coûte cher.
+21,Mon jardin me procure une joie simple que je ne trouve nulle part ailleurs.
+22,Les jeunes d'aujourd'hui travaillent autant que nous mais dans des conditions différentes.
+23,Je remercie chaque jour la vie pour la bonne santé de mes proches.
+24,Perdre mon emploi m'a obligé à repenser complètement toutes mes priorités.

sample_data/latin1_encoding_demo.csv

@@ -0,0 +1,11 @@
+id,text
+1,I met my fianc�e at a caf� near the university and we talked until closing.
+2,Updating my r�sum� after ten years at one company felt strangely emotional.
+3,The na�ve optimism of my twenties has mellowed into something more durable.
+4,We celebrated the sale with cr�me br�l�e at the bistro around the corner.
+5,My prot�g� at work just got promoted and I could not be prouder.
+6,The expos� in the local paper finally forced the council to act.
+7,Our s�ance-themed escape room birthday party was ridiculous and absolutely perfect.
+8,He runs a small atelier restoring antique furniture with his p�re.
+9,A d�tour through the mountains added three hours and the best views of the trip.
+10,The caf�'s terrace overlooks the plaza where we watched the parade every ann�e.

sample_data/long_documents_demo.csv

@@ -0,0 +1,11 @@
+id,text
+1,"When I look back at the last decade of my life I see a person who kept postponing every meaningful decision while telling himself that the right moment would arrive on its own, and the strange thing is that the moment never announced itself, it simply passed by quietly while I was busy answering emails and attending meetings that could have been messages, and it took a health scare in the winter of last year for me to finally sit down with a notebook and write out what I actually wanted from the years that remain, which turned out to be embarrassingly simple things like living near my sister, working four days a week instead of six, learning to cook the dishes my mother used to make, and spending unhurried afternoons with people I love instead of networking events with people I barely tolerate, and since that evening I have slowly been rearranging my life around that short list, canceling subscriptions and obligations that serve no one, and although the process is far from finished I can already feel a kind of quiet returning to my mornings that I had not felt since I was a student, when time still seemed like something I owned rather than something I owed to other people, and that alone convinces me the effort has been worth it."
+2,"When I look back at the last decade of my life I see a person who kept postponing every meaningful decision while telling himself that the right moment would arrive on its own, and the strange thing is that the moment never announced itself, it simply passed by quietly while I was busy answering emails and attending meetings that could have been messages, and it took a health scare in the winter of last year for me to finally sit down with a notebook and write out what I actually wanted from the years that remain, which turned out to be embarrassingly simple things like living near my sister, working four days a."
+3,"The company restructuring was announced on a Tuesday morning through a calendar invite with no agenda, and within an hour the office had split into small anxious clusters trading theories, and I remember standing by the window thinking about how much of my identity I had quietly invested in a job title that could be deleted by a spreadsheet formula in a conference room three time zones away, and in the weeks that followed, as colleagues I respected packed their desks into cardboard boxes, I started keeping a journal for the first time in my adult life, mostly to have somewhere to put the sentences I could not say in meetings, and what surprised me was how quickly the writing stopped being about the layoffs and started being about everything else, my marriage, my health, the friendships I had let thin out to nothing, the guitar in the closet, and by the time my own meeting invitation arrived in spring I had already built a version of myself that did not live entirely inside that building, so when they told me my role was being eliminated I felt fear, certainly, but underneath it something closer to relief, like a door I had been leaning against for years had finally been opened from the other side, and I walked out into the parking lot genuinely curious about what would happen next."
+4,"The company restructuring was announced on a Tuesday morning through a calendar invite with no agenda, and within an hour the office had split into small anxious clusters trading theories, and I remember standing by the window thinking about how much of my identity I had quietly invested in a job title that could be deleted by a spreadsheet formula in a conference room three time zones away, and in the weeks that followed, as colleagues I respected packed their desks into cardboard boxes, I started keeping a journal for the first time in my adult life, mostly to have somewhere to put the sentences I could not say in meetings, and what."
+5,"When I look back at the last decade of my life I see a person who kept postponing every meaningful decision while telling himself that the right moment would arrive on its own, and the strange thing is that the moment never announced itself, it simply passed by quietly while I was busy answering emails and attending meetings that could have been messages, and it took a health scare in the winter of last year for me to finally sit down with a notebook and write out what I actually wanted from the years that remain, which turned out to be embarrassingly simple things like living near my sister, working four days a week instead of six, learning to cook the dishes my mother used to make, and spending unhurried afternoons with people I love instead of networking events with people I barely tolerate, and since that evening I have slowly been rearranging my life around that short list, canceling subscriptions and obligations that serve no one, and although the process is far from finished I can already feel a kind of quiet returning to my mornings that I had not felt since I was a student, when time still seemed like something I owned rather than something I owed to other people, and that alone convinces me the effort has been worth it. I have retold this story to myself so many times that the details have worn smooth like river stones, and I no longer know which parts are memory and which parts are the polish."
+6,Losing my father last year made me rethink what actually matters in life. My therapist helped me see that resting is not the same thing as failing. Passing the certification exam after two failed attempts felt absolutely incredible.
+7,"The company restructuring was announced on a Tuesday morning through a calendar invite with no agenda, and within an hour the office had split into small anxious clusters trading theories, and I remember standing by the window thinking about how much of my identity I had quietly invested in a job title that could be deleted by a spreadsheet formula in a conference room three time zones away, and in the weeks that followed, as colleagues I respected packed their desks into cardboard boxes, I started keeping a journal for the first time in my adult life, mostly to have somewhere to put the sentences I could not say in meetings, and what surprised me was how quickly the writing stopped being about the layoffs and started being about everything else, my marriage, my health, the friendships I had let thin out to nothing, the guitar in the closet, and by the time my own meeting invitation arrived in spring I had already built a version of myself that did not live entirely inside that building, so when they told me my role was being eliminated I felt fear, certainly, but underneath it something closer to relief, like a door I had been leaning against for years had finally been opened from the other side, and I walked out into the parking lot genuinely curious about what would happen next. What I did not expect was that the curiosity would outlast the severance package, and that a year later I would still wake up early, not from anxiety, but from wanting to get started."
+8,Work has been stressful lately but my manager actually listens when I raise problems. The commute drains me but the job itself is genuinely interesting work. I have not taken a real vacation in three years and it shows.
+9,Moving to a smaller town was the best decision my partner and I ever made. I feel disconnected from old friends who moved away after graduation.
+10,The new morning routine with exercise and journaling has changed how my days feel. Cooking dinner from scratch most nights has become a small daily victory.

sample_data/mixed_language_demo.csv

@@ -0,0 +1,31 @@
+id,text
+1,I have been feeling much more optimistic about the future these past few months.
+2,Estoy muy contento con mi trabajo nuevo y mis compañeros son amables conmigo.
+3,My weekends are finally my own again and I spend them hiking with friends.
+4,"La familia siempre está primero, no importa lo que pase en la vida."
+5,Work has been stressful lately but my manager actually listens when I raise problems.
+6,Ayer caminé por el parque y me sentí tranquilo por primera vez en semanas.
+7,I started volunteering at the food bank and it gives my week a sense of purpose.
+8,Necesitamos ayudar a los que sufren porque es nuestra responsabilidad moral más importante.
+9,Moving to a smaller town was the best decision my partner and I ever made.
+10,Cada persona merece un trato justo sin importar de dónde venga su familia.
+11,Some days I feel like I am just going through the motions without any direction.
+12,Mis abuelos me enseñaron el valor del esfuerzo y de la honestidad.
+13,My savings finally reached the point where an emergency would not ruin me.
+14,La ciudad ha cambiado mucho pero sigue siendo mi hogar querido.
+15,I wish I had more time to read books instead of scrolling on my phone.
+16,Después de la enfermedad aprendí a valorar cada día como un regalo.
+17,The new morning routine with exercise and journaling has changed how my days feel.
+18,El respeto a los mayores es una tradición que debemos conservar siempre.
+19,Losing my father last year made me rethink what actually matters in life.
+20,Trabajo muchas horas pero al final del día me siento orgulloso.
+21,I am proud of how my children treat other people with kindness and patience.
+22,La lealtad entre amigos verdaderos es lo más valioso que existe.
+23,The neighborhood association finally fixed the park and kids play there every evening.
+24,Me preocupa que los jóvenes pierdan las costumbres de nuestro pueblo.
+25,I keep comparing myself to classmates who seem far more successful than me.
+26,Cocinar para mi familia los domingos es mi momento favorito de la semana.
+27,Cooking dinner from scratch most nights has become a small daily victory.
+28,La honestidad cuesta cara pero dormir tranquilo no tiene precio ninguno.
+29,My therapist helped me see that resting is not the same thing as failing.
+30,Sueño con volver al pueblo donde nací y abrir una pequeña tienda.

sample_data/moral_foundations_demo.csv

@@ -0,0 +1,43 @@
+id,text
+1,Seeing an injured animal on the road makes me pull over to help every single time.
+2,I cannot walk past a crying child without stopping to make sure they are okay.
+3,Our society should be judged by how gently it treats its weakest members.
+4,I donate blood regularly because someone out there is suffering and I can help.
+5,Hurting someone who cannot defend themselves is the worst thing a person can do.
+6,I chose nursing because easing another person's pain feels like my calling.
+7,Everyone deserves the same opportunities no matter what family they were born into.
+8,It bothers me deeply when some groups are treated as second class citizens.
+9,A fair society makes sure nobody is left too far behind the rest.
+10,I support policies that close the gap between the richest and the poorest.
+11,"All voices in the meeting should get equal time, not just the loudest ones."
+12,No one is above the law and no one should be beneath its protection.
+13,People who work harder deserve to earn more than those who slack off.
+14,Cheaters should be punished in proportion to the harm they caused.
+15,Bonuses should go to the employees who actually delivered the results.
+16,It is wrong when someone takes credit for work they did not do.
+17,Students who study hardest have earned the top grades they receive.
+18,Rewards mean nothing if they are handed out equally regardless of effort.
+19,I would defend my hometown team even in a losing season.
+20,Betraying your own family is something I could never forgive.
+21,When my country is criticized abroad I feel personally insulted.
+22,I stuck with my old company through the hard years out of loyalty.
+23,True friends stand by each other even when it costs them something.
+24,Leaving your group when times get tough is a form of betrayal.
+25,Children should be taught to respect their teachers and elders.
+26,A team works best when everyone respects the chain of command.
+27,I always address judges and officers with the respect their position deserves.
+28,Traditions passed down by our elders hold wisdom we should not discard.
+29,Soldiers who disobey lawful orders put everyone around them in danger.
+30,"Questioning authority has its place, but constant defiance destroys institutions."
+31,Some things are sacred and should never be treated as commodities.
+32,I keep my body clean and healthy because it feels like a temple.
+33,Certain acts are degrading even if nobody is directly harmed by them.
+34,"There is something deeply wrong about desecrating a grave, even an unmarked one."
+35,I fast twice a year to cleanse both my body and my mind.
+36,Crude jokes about sacred rituals make me genuinely uncomfortable.
+37,The bus to the office takes about forty minutes on weekday mornings.
+38,I usually buy groceries on Sunday because the store is less crowded.
+39,The printer on the third floor has been out of toner since Tuesday.
+40,My apartment gets good afternoon light in the summer months.
+41,The weather forecast says light rain for most of the weekend.
+42,I switched my phone plan last month to one with more data.

sample_data/multi_column_demo.csv

@@ -0,0 +1,15 @@
+id,author,comment_text,created_at,upvotes
+1,km_reader,"The pacing in the middle chapters drags, but the ending redeems the whole book.",2026-05-02,14
+2,sofia_v,"Honestly the best library branch in the city, quiet and the staff remember your name.",2026-05-03,32
+3,brownstone88,"Parking situation got worse after the redesign, twenty minutes circling yesterday.",2026-05-03,7
+4,elena,"The volunteer program changed my retirement, I feel useful again three days a week.",2026-05-04,41
+5,marcusJ,"Terrible communication from the landlord, three weeks without a working elevator.",2026-05-05,19
+6,quiethiker,Sunrise from the east ridge trail is worth every step of the climb.,2026-05-06,55
+7,pat_the_cook,New farmers market vendor sells the best sourdough I have had in years.,2026-05-07,23
+8,rlopez,The clinic doubled its wait times but the nurses are still wonderful people.,2026-05-08,11
+9,greenthumb,"My tomatoes failed again this year, the soil in this neighborhood is just clay.",2026-05-09,5
+10,nightowl_dev,Working remotely from the cafe on Fifth has made my weeks so much better.,2026-05-10,28
+11,amina,"The community garden waitlist is two years long now, which says something lovely about us.",2026-05-11,37
+12,tomk,Bike lanes on the bridge finally opened and my commute dropped by fifteen minutes.,2026-05-12,46
+13,harriet_b,The museum's free Thursday evenings are the best kept secret in town.,2026-05-13,30
+14,dgupta,"Street noise has gotten unbearable since the venue opened, considering moving after eight years.",2026-05-14,16

sample_data/semicolon_delimited_demo.csv

@@ -0,0 +1,13 @@
+id;text
+1;For me, happiness is a quiet morning, strong coffee, and nowhere to be.
+2;After the diagnosis, my priorities shifted overnight: family first, career second, everything else third.
+3;We saved for years, skipped vacations, and finally bought the little house by the river.
+4;My mentor taught me three things: listen first, decide slowly, and apologize quickly.
+5;The move was chaotic, exhausting, and expensive, but it was absolutely the right call.
+6;I volunteer on Saturdays, garden on Sundays, and somehow the week feels balanced now.
+7;Losing the match hurt, but watching my teammates support each other made me proud.
+8;"Retirement scared me at first; now my days are fuller than they ever were."
+9;She speaks four languages, runs marathons, and still calls her mother every evening.
+10;The old neighborhood had noise, cracked sidewalks, and the kindest people I have ever known.
+11;Budget cuts closed the library branch, the pool, and half the after-school programs.
+12;Grief comes in waves: some days are calm, others knock me completely off my feet.

sample_data/warnings_showcase.csv

@@ -0,0 +1,34 @@
+id,text
+1,I have been feeling much more optimistic about the future these past few months.
+2,My weekends are finally my own again and I spend them hiking with friends.
+3,Work has been stressful lately but my manager actually listens when I raise problems.
+4,I started volunteering at the food bank and it gives my week a sense of purpose.
+5,Moving to a smaller town was the best decision my partner and I ever made.
+6,Some days I feel like I am just going through the motions without any direction.
+7,
+8,My savings finally reached the point where an emergency would not ruin me.
+9,I wish I had more time to read books instead of scrolling on my phone.
+10,The new morning routine with exercise and journaling has changed how my days feel.
+11,Losing my father last year made me rethink what actually matters in life.
+12,I am proud of how my children treat other people with kindness and patience.
+13,The neighborhood association finally fixed the park and kids play there every evening.
+14,yes
+15,I keep comparing myself to classmates who seem far more successful than me.
+16,Cooking dinner from scratch most nights has become a small daily victory.
+17,My therapist helped me see that resting is not the same thing as failing.
+18,We adopted an older dog and the house feels alive again.
+19,
+20,I have not taken a real vacation in three years and it shows.
+21,Passing the certification exam after two failed attempts felt absolutely incredible.
+22,Most evenings I call my grandmother and we talk about her garden.
+23,The commute drains me but the job itself is genuinely interesting work.
+24,I finally paid off my student loans after nine long years.
+25,Sometimes the city noise makes it impossible to hear my own thoughts.
+26,Teaching my daughter to ride a bike was the highlight of my month.
+27,I feel disconnected from old friends who moved away after graduation.
+28,ok fine
+29,not really sure
+30,I have been feeling much more optimistic about the future these past few months.
+31,I started volunteering at the food bank and it gives my week a sense of purpose.
+32,"When I look back at the last decade of my life I see a person who kept postponing every meaningful decision while telling himself that the right moment would arrive on its own, and the strange thing is that the moment never announced itself, it simply passed by quietly while I was busy answering emails and attending meetings that could have been messages, and it took a health scare in the winter of last year for me to finally sit down with a notebook and write out what I actually wanted from the years that remain, which turned out to be embarrassingly simple things like living near my sister, working four days a week instead of six, learning to cook the dishes my mother used to make, and spending unhurried afternoons with people I love instead of networking events with people I barely tolerate, and since that evening I have slowly been rearranging my life around that short list, canceling subscriptions and obligations that serve no one, and although the process is far from finished I can already feel a kind of quiet returning to my mornings that I had not felt since I was a student, when time still seemed like something I owned rather than something I owed to other people, and that alone convinces me the effort has been worth it."
+33,"The company restructuring was announced on a Tuesday morning through a calendar invite with no agenda, and within an hour the office had split into small anxious clusters trading theories, and I remember standing by the window thinking about how much of my identity I had quietly invested in a job title that could be deleted by a spreadsheet formula in a conference room three time zones away, and in the weeks that followed, as colleagues I respected packed their desks into cardboard boxes, I started keeping a journal for the first time in my adult life, mostly to have somewhere to put the sentences I could not say in meetings, and what surprised me was how quickly the writing stopped being about the layoffs and started being about everything else, my marriage, my health, the friendships I had let thin out to nothing, the guitar in the closet, and by the time my own meeting invitation arrived in spring I had already built a version of myself that did not live entirely inside that building, so when they told me my role was being eliminated I felt fear, certainly, but underneath it something closer to relief, like a door I had been leaning against for years had finally been opened from the other side, and I walked out into the parking lot genuinely curious about what would happen next."