docs: correct install and MCP onboarding counts

[Birfy]

What changed

• Update the install guide's dry-run count to 20, matching the 8 benchmark-faithful ports, 11 MethodPolicy ports, and Genesis.
• List all 15 registered MCP tools in the standalone MCP walkthrough, grouped in the prose as eight run-lifecycle tools and seven audit tools.
• Add checks that compare the install-guide count to the canonical port catalog and the MCP guide names to TOOL_DESCRIPTIONS.

This is a docs and regression-test slice. It does not change runtime behavior or touch the overlapping async, ledger, or aggregator work in open PRs.

Verification

• Exact-head CI passed at 888bef1e2aa6b16288d5e2dc647f8e5abcdb72fb: tests workflow matrix on Python 3.9, 3.10, 3.11, 3.12 (including build and wheel smoke); strict docs build passed. Docs deploy skipped for the PR as expected.
• Focused local guide/registry checks: 3 passed, 1 skipped (MCP SDK server integration unavailable on local Python 3.9).
• Local git diff --check: passed.
• Local mkdocs build --strict cannot complete because cairosvg is absent; exact-head docs CI passed with the workflow dependencies.
• One local run of the existing MCP end-to-end flow test ended in failed instead of done; the full exact-head CI suite passed on all supported matrix versions.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-09T23:25:35.108118Z	888bef1	Draft marked ready

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