docs(web): trim site copy, add benchmark charts

[karngyan]

Why

reins.tech/docs/benchmarks was about 1,300 lines of source: a 38-row, 12-column table, round-by-round tuning history and commit hashes. Nobody could read it on a page. The other pages had the same problem on a smaller scale: the same facts said twice, and long sentences.

What

Benchmarks. Cut to a short summary. The per-task tables, method, tuning history, reverted experiments and limitations all still live in docs/benchmarks/2026-09-reins-do.md, and the page links to it at the end. It adds two charts, in plain HTML/CSS in components/bench-charts.tsx:

• Runs passed: bars for reins do vs Claude, on the unseen tasks and the tuned tasks.
• Time per task: a dumbbell per task for the 30 tasks both passed. Hovering a row shows its medians and speed-up.

reins do uses the site violet and Claude uses orange. The pair passes the colorblind-separation and 3:1 contrast checks on both themes. Both charts have screen-reader text.

Other pages:

• Homepage: the install commands, the shared flags and the "0.x" note were each said twice; now once. The facts table goes from 10 rows to 4.
• Security: the reins do section is about half as long. It still lists every field sent to TypeSafe and every safety check.
• Comparison: four 6-row tables become two short paragraphs per tool.
• FAQ, getting started, commands, permissions, architecture: shorter sentences, no facts removed.

The anchors other files link to (security#reins-do, commands#delegate) are kept.

Testing

• The web build passes. check-prose reports no dashes. Typecheck passes, and biome passes on packages/web.
• pnpm lint at the root currently fails only on untracked packages/extension/store-assets/screens/ files. Those aren't part of this PR.
• Checked screenshots of the homepage and the benchmarks page at 1280px and 400px.

🤖 Generated with Claude Code