docs(readme): make it scannable without deleting a word

[0bserver07]

The README's structure was never the problem — Who This Is For → What It Does → How It Works → Install → Build Your Own is a good spine. Three specific places dumped everything at once.

What changed

1. The Status line was one 1,049-character sentence. Test counts, a posture caveat, four benchmark scores, the depth matrix, a feature list, and two links, all in a single run-on paragraph. Now: a one-line status, a scoreboard table, and a collapsible note explaining why there are two test numbers.

2. "New in 0.9.0" was four releases stale. Now leads with 0.9.2.3. The multiplexer keeps its entire section, retitled "Race N agents on one task" — it's still true and still the mission, it just isn't new.

3. Six codename CLIs were 152 lines, 35% of the file. Near-identical sections stacked back to back. Now <details> blocks, so a reader sees six one-line pitches and opens the one they care about:

▸ Otter  — server-first coding agent
▸ Ferret — sandbox-first IDE-flagship coding agent
▸ Weasel — minimal harness with four operating modes
▸ Shrew  — tuned for small local models
▸ Stoat  — shell-mode-toggle coding agent
▸ Badger — harness-rewrite coding agent

Nothing was deleted

	before	after
file	433 lines / 27,892 chars	498 lines / 28,611 chars
visible before expanding	433	365
one click away	—	133

The file is 719 characters larger. Less is shown; nothing is gone.

Verified, not asserted. A line-by-line diff against the previous README reports exactly six absent lines — all six the ### Name — description headings that became <summary><b>Name</b> — description</summary>, with each description confirmed present verbatim. No document in README.md, docs/ or site/ links the anchors those headings provided.

The tagline is byte-identical, checked programmatically rather than by eye. Changing taglines isn't mine to do.

Gates: claims + repo-hygiene 75 passed (the claims gate scans README.md, so the new benchmark table is checked against its receipts).

🤖 Generated with Claude Code