feat: add Cost column to leaderboard (aggregate per-run cost)

data: add metadata for remaining 14 benchmarked models

feat: add dark-theme HTML leaderboard template

feat: add --html flag and render_html to leaderboard generator

feat: add model metadata sidecar + merge for leaderboard

chore: move NEET 2026 chart generator into gitignored charts/

charts: declutter cost-vs-accuracy plot

charts: register Gemma 4 31B IT display name

charts: register Gemini 3.1 Flash Lite display name

results: Kimi K2.5 on NEET 2026 — 705/720 (97.9%)

results: Mistral Medium 3.5 on NEET 2026 — 402/720 (55.8%)

fix(charts): readable cost axis and label spacing on cost-vs-accuracy

scripts: add Grok 4.3 display name and color to chart generator

fix(charts): point watermark to huggingface.co dataset URL

scripts: add NEET 2026 chart generator

scripts: add patch_one_question.py for re-running single failed questions

fix: leaderboard handles all-exam/all-year runs via summary.jsonl fallback

Add reproducibility controls, leaderboard, and contamination disclosure