Add a human-merge label that keeps autopilot from merging

autopilot skips both human checkpoints: approval before the build and the
merge. Scheduled update issues in homelab want the hands-off build but a human
merge, since merging there deploys. With human-merge also on the issue, @pm is
told to hand back at phase 3 and publish.sh refuses MERGE_PR.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

AGENTS.md

@@ -29,6 +29,8 @@ An issue labeled **`autopilot`** runs without the usual human checkpoints:
 - **Kill switch:** remove the `autopilot` label at any time. The label is re-read fresh at the
   start of every run, so the next agent turn reverts to normal human-approval behavior. `@qa` also
   removes the label itself whenever it halts on a bug or a failed merge.
+- **`human-merge` label** (together with `autopilot`): everything above except the merge — after
+  `@qa` approves, `@pm` tells the creator the PR is ready and a human merges.
 No label (the default) = today's behavior, unchanged.
 
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