rafaie/codex_home/release-prep

1) Read AGENTS.md, codex.toml, release identifier/scope, spec/changelog.md, and status/evidence for included work items. 2) Require every included work item to be Ready to ship or explicitly excluded with rationale. 3) Run test-runner in full mode as the single owner of release checks and applicable smoke. 4) Stop if any stage fails; record the failure without finalizing release notes. 5) For runnable release paths, validate the current-source smoke artifact contract and evidence identity used by ship-feature. 6) Finalize the release section in spec/changelog.md, verify README.md, and summarize included work items, breaking changes, migrations, and evidence paths. 7) Mark included work items Done only after the release/merge action is confirmed; otherwise leave them Ready to ship.