docs: state the goal in a testable form and stop carrying counts

[fdaviddpt]

Closes #1396.

The problem this fixes

docs/overview.md is where this project states what it is for, and it had drifted on five separate
numbers -- commands (8 against 9), agents (5 against 6), phase files (6 against 9), scripts (40
against 86), and the sub-manager's handback states (three against six) -- plus a standing table
dated 2026-09-02 at v0.17.0, carried through fourteen tags.

Every sentence was correct when written. That is the point: it read as current the whole time, which
is this project's own defect class applied to its own prose.

The fix is not to correct the counts

It is to stop carrying them. A goal document that holds no countable fact cannot drift into a wrong
one, and ls is the source of truth for how many commands there are. A page that duplicates it is a
second copy to keep in sync forever, which is the thing the governing rule forbids.

What the page carries now

• No counts, and a sentence saying why.
• Four tests for whether work is inside the goal -- does it resolve issues or maintain
  machinery; does it remove a human from the loop or add one; does it leave a second copy of a fact;
  can it tell "found nothing" from "could not look". Work failing one is outside the goal even when
  correct, reproducible and asked for. This is what the page was asked for and did not previously do:
  a boundary test on live work, not a description.
• The surface -- two verbs, marked as not built yet, and the loop-not-router rule (One entry point: /oss:run asks what this repo needs now #1389).
• What runs underneath -- framed as internal vocabulary that need not reach the user surface.
• Cadence is config, not memory (The triage sweep after a release is stated as a rule and implemented by nothing #1386).
• Where prose lives -- one destination per kind of thing learned, chosen by what each destination
  costs rather than by subject.
• What is not true yet -- the triage gap, no unattended runtime, and that the loop has only ever
  run in front of the person who wrote it.

Known gap, deliberately not fixed here

The surface section starts at the slash picker. The honest surface starts at the launcher -- install
the plugin, run oss-workspace, it works -- since nobody normally types either verb. #1392 records
that and owns the fix.

Checks run

• assemble_changelog.py --check -- ok, both fragments parse.
• tests/test_claude_md_currency.py, tests/test_content_invariants.py,
  tests/test_docs_state_slug_grammar_308.py -- 226 passed.
• markdownlint via the write validator: 39 errors before this change, 5 after, all remaining ones
  table rows too wide to wrap.

Docs only. No code path changes.

🤖 Generated with Claude Code

https://claude.ai/code/session_012UYdzDHX3k3C2Eh7B5hRVH

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