The weekly restore drill posts its verdict on the recovery issue, and a failed drill is a card in the inbox #1481

Split from #1219 (a person's ask). The weekly drill itself (restore the newest snapshot into an empty directory, open it, read its sealed values) is #1182. This issue is what #1219 added on top: telling people.

Done looks like.

• [ ] When #1182's drill finishes, it posts one comment on this repository's recovery issue. The comment gives the snapshot name, how long the restore took, health, counts (repositories, issues) and pass or fail.
• [ ] The drill also boots the restored directory on a side port and reads /api/v1/health before it passes.
• [ ] A failed drill is an inbox card for the owner naming the step that failed, and the next passing drill clears the card.
• [ ] docs/RECOVERY.md (#1219's split) says where the verdicts are posted.
• [ ] A test (named in GATE) proves that a stand-in drill posts the comment and that a failing one makes the card. Before the pull, run it and bun test test/check-list.test.ts in the sandbox.

Files. the drill's module from #1182, the inbox card source, docs/RECOVERY.md, a new test, scripts/gate.ts. Fits: scout.