finalize distribution prep closeout

[xiaojiou176]

Summary

• replace the old weekly governance lane with the current manual plus runtime-gc model and sync the related docs/tests
• add concentrated distribution and integration truth surfaces without overclaiming registry publication
• align storefront closure checks with the live GitHub Pages, Issues, Discussions, and branch-protection truth

Test Plan

• ./scripts/security-scan.sh
• pnpm public:truth:check
• bash scripts/docs-gate.sh
• pnpm docs:governance:check
• bash scripts/tests/github-closure-evidence-smoke.sh
• node --test scripts/ci/workflow-policy.test.mjs scripts/ci/run-in-container.test.mjs
• node --import tsx --test apps/mcp-server/tests/mcp-smoke.test.ts
• bash scripts/github/check-storefront-settings.sh --json
• python3 scripts/github/collect-closure-evidence.py --pretty

Breaking Changes

None

Rollout / Risk

• Risk level: Medium
• Rollout: merge to main after PR gate is green and one review is recorded
• Rollback: revert the merge commit, then rerun the validation commands above
• Monitoring: PR gate, repo truth surfaces, storefront closure evidence, security scan

Checklist

• Self-reviewed code
• No debug/print statements left
• Documentation updated where public behavior or governance changed
• Validation commands recorded above
• Every commit includes a Signed-off-by line