feat(claude-code): update placemat for Claude Code v2.1.292

[dommango]

Summary

• npm dist-tags.latest is v2.1.292, cross-checked against code.claude.com/docs/en/changelog. v2.1.291 (also released 2026-10-06) was a bug-fix-only maintenance release with nothing placemat-relevant, so it gets no changelog entry — the header's "As of release" tag moves straight from v2.1.291 to v2.1.292.
• Added claude plugin install <plugin> to card-skills's "Plugin CLI Commands" group (it had no row before), documenting its existing scope/yes/json flags plus the new v2.1.292 flag --marketplace <source> (adds the marketplace if needed, then installs from it).
• Added env var CLAUDE_CODE_OVERLOADED_RETRY_BASE_DELAY_MS to card-env's "All Variables" group — lengthens the base backoff delay for retrying an overloaded (529) request.
• Added a note to the existing MCP_PROTOCOL_NEGOTIATION=legacy row: local (stdio) MCP connections now negotiate protocol 2026-07-28 by default on every install, not just Bedrock/Vertex/Foundry/telemetry-disabled as before.
• --marketplace <source> and CLAUDE_CODE_OVERLOADED_RETRY_BASE_DELAY_MS are confirmed verbatim in the v2.1.292 changelog but not yet in plugins/cli-reference.md / env-vars.md respectively — included per the release_notes rule, with gotchas recorded in sources.json to re-check those reference pages on a future sync.
• Re-extracted sources.json → inventory (bumped fetched to 2026-10-07): no new slash command, settings key, or JSON-lifecycle hook event in this release. The release's new mod-authoring-API hook events (prompt.autocomplete, agent.spawn, tool.check, config.set/state.set/env.set) belong to the separate JS/TS Mods API, which the placemat has no card group for yet — left out of this sync and noted for a future one, rather than force-fit into the existing Event Hooks group.
• Updated changelog.html (new v2.1.292 entry inside the October 2026 group, now 4 releases), the .release-tag/.print-head pair, and the footer Content synced date — all three agree at 2026-10-06, the newest changelog release's date.
• Regenerated changes.json and feed.xml via node scripts/build-changes.js claude-code.

Checklist

• node scripts/build-changes.js claude-code — regenerated clean
• node tests/placemat.test.js claude-code — 54 passed, 0 failed
• Per-page parity (release tag / print-head / footer sync date) verified equal
• Row ids are new permalinks, no existing i- id changed
• No class="new" written; no fabricated content — both new flag items sourced from the vendor changelog, with gotchas flagging the not-yet-in-reference-page caveat
• Self-review for technical accuracy against sources and consistency with other cards

🤖 Generated with Claude Code

https://claude.ai/code/session_01Ego5fk2R685cYTsBXC2rGA

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Generated by Claude Code

[dommango]

Merge-gate code review (Step 10)

Ran the code-review skill against this PR's diff, independent of the Step 8 self-review.

Verdict: clean — no findings.

Checked: full test suite (54/54 pass), generator staleness (build-changes.js --check up to date), row-id slug derivation, notes +N counts vs <li> counts, per-page parity (release tag / print-head / footer sync date all agree at 2026-10-06), changelog month-count/version-range vs actual headings, changes.json/feed.xml are faithful generator output, no cross-agent-directory changes, no duplicate row ids, no class="new" introduced, no vendor-logo/brand issues, new rows/notes consistent with their sources.json gotchas.

No CRITICAL/HIGH finding → proceeding to merge once CI is green.

🤖 Generated with Claude Code

https://claude.ai/code/session_01Ego5fk2R685cYTsBXC2rGA

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Generated by Claude Code