Make dataset card semantics match live Viewer (#3)

- Make dataset card semantics match live Viewer (d4d2b5fe34c818525032863070deeeb96314912f)

README.md

@@ -7,6 +7,8 @@ source_datasets:
 - original
 size_categories:
 - n<1K
+task_categories:
+- feature-extraction
 tags:
 - video
 - time-series
@@ -19,21 +21,19 @@ tags:
 
 # time-lapse-artifacts
 
-An active longitudinal archive of analog drawing process.
+467 time-lapse recordings of analog drawing from one continuous practice,
+covering September 2024–present (currently through August 10, 2026). The active
+release is approximately 1.89 TB: 338 canonical Standard videos with per-record
+content hashes and validated technical metadata, plus 129 earlier Pre-Standard
+recordings with lighter descriptive metadata.
 
-**Archive scope:** 2012–Present  
-**Currently published video coverage:** September 2024–Present  
-**Release status:** Active construction release
-
-The archive scope describes the underlying recording practice and holdings. It
-does not mean that recordings from every year have been published. In the
-audited 2026-08-18 snapshot, published video rows begin in September 2024; the
-2012–2016 livestream layer has not yet been ingested as public video data.
+The underlying practice also includes a 2012–2016 livestream layer, but those
+videos are not yet published. This is an active construction release.
 
 ## Snapshot and Coverage
 
-This documentation was audited against repository commit
-`339e6149de130cbe2d001f7a0e5247872bc788ec`.
+This documentation describes merged repository revision
+`3967721ce363316cb7475be648af34a66bc83c27` and the live Viewer rebuilt from it.
 
 | Collection tier | Published MP4s | Indexed rows | Date coverage | Metadata state |
 | --- | ---: | ---: | --- | --- |
@@ -41,18 +41,40 @@ This documentation was audited against repository commit
 | `pre_standard` | 129 | 129 | 2024-09-17–2025-07-13, plus 9 unknown dates | Filename-level descriptive metadata; technical ingestion incomplete |
 | `legacy_livestream` | 0 public videos | 0 | Historical scope 2012–2016 | Placeholder layer; ingestion pending |
 
-At the pinned base revision, the Hub Viewer exposes 465 rows: 335 standard
-rows and 130 pre-standard metadata rows. Audit found that one pre-standard row
-referred to material that is not distributed because the required ownership
-and provenance threshold was not met. This release removes that row from the
-active public index. This release also indexes three previously unindexed
-Standard files, leaving 338 standard and 129 pre-standard rows and an expected
-467 active Viewer rows after rebuild.
+**Current published index (v0.2):** the live Hub Viewer exposes 467 rows: 338
+Standard and 129 Pre-Standard. The preceding v0.1 state at revision
+`339e6149de130cbe2d001f7a0e5247872bc788ec` exposed 465 rows: 335 Standard and
+130 Pre-Standard. v0.2 added three previously unindexed Standard files and
+removed one Pre-Standard row whose media did not meet the ownership and
+provenance threshold. The rebuild is complete; 467 is the current state, not a
+pending estimate.
 
 The builder-generated split name `train` is an archive-loading default,
 **not** a recommended machine-learning train split. No official
 train/validation/test partition has been defined.
 
+## Viewer and Metadata Discovery
+
+The current Hub build automatically discovers and loads **both** metadata
+files into one `default/train` Viewer split:
+
+- root `metadata.csv` indexes the 338 direct files in
+  `Standard_Time_Lapses/`
+- `Pre_Standard_Time_Lapses/metadata.csv` indexes the 129 direct files in that
+  folder
+
+The Viewer therefore has 467 rows and a 29-column union schema. Fields that do
+not exist in the lighter Pre-Standard CSV appear as null on those 129 rows;
+their membership is defined by the folder-local index and `video` path. The
+root canonical CSV explicitly sets `collection_tier = standard`; the current
+Pre-Standard CSV does not yet populate that column.
+
+There is no explicit `configs:` block in this release. A broad canonical
+folder glob could accidentally include the nested
+`Standard_Time_Lapses/Provenance/` subtree. Separate canonical and
+Pre-Standard configurations therefore remain a fail-closed migration task
+described in `VIEWER_MIGRATION.md`, rather than an untested card-only change.
+
 ## Overview
 
 `time-lapse-artifacts` documents analog drawing processes across different
@@ -108,6 +130,9 @@ published for archival continuity but are not interchangeable with canonical
 standard records. Their technical metadata remains incomplete. Missing values
 must not be interpreted as zero, false, or evidence that a property was absent.
 
+The folder-local `metadata.csv` is the active index for these 129 videos and is
+loaded by the current Viewer alongside the root canonical index.
+
 Material that does not meet the archive's ownership and provenance threshold
 is excluded from both the published media and the active metadata index.
 
@@ -133,9 +158,11 @@ relationships, and unresolved information. Evidence may include:
 Uncertain relationships are not promoted to verified relationships solely
 because dates or filenames look similar.
 
-Multiple `tool` and `medium` values use semicolons. The two fields are
-independent observed-value lists; equal list lengths and positional pairing are
-not guaranteed. See `SCHEMA.md`.
+The active CSV files and live Viewer use semicolons for multiple `tool` and
+`medium` values, for example `Pencil;FountainPen` and `Graphite;Ink`. A pipe
+(`|`) is **not** a valid separator in v0.2. The two fields are independent
+observed-value lists; equal list lengths and positional pairing are not
+guaranteed. See `SCHEMA.md`.
 
 `encoded_frame_rate` is encoded playback rate. It is not the original temporal
 sampling rate of the drawing process.
@@ -223,7 +250,8 @@ the archival masters.
 
 ## Access and Reproducibility
 
-The archive is approximately 1.86 TB. Canonical files are often several
+The active 467-video release contains 1,885,402,632,655 bytes of video
+(approximately 1.89 TB, or 1.71 TiB). Canonical files are often several
 gigabytes each, so users should select records through `metadata.csv` before
 downloading video.