heartbeat: 55-minute job, and the claude seat's token for reviews

The job timeout moves from 20 to 55 minutes: workers can overlap inside one run (#75), and at 20 every in-flight worker died together. TIME_SEAT_CLAUDE reaches the heartbeat so the reviewer can post as the `claude` user once #76 lands; until then it is unused.

Both on the owner's explicit instruction (CEO session).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017K4vyY3yUD3GsvoZaAtKkD

.github/workflows/heartbeat.yml

@@ -24,7 +24,7 @@ jobs:
         (startsWith(github.event.comment.body, '**Approve') || startsWith(github.event.comment.body, 'Approve') ||
          startsWith(github.event.comment.body, '**Object') || startsWith(github.event.comment.body, 'Object'))))
     runs-on: ubuntu-latest
-    timeout-minutes: 20
+    timeout-minutes: 55   # workers can overlap inside one job now (#75); under the hourly cadence, and the concurrency group queues the next run
     steps:
       - uses: actions/checkout@v5
         with:
@@ -37,6 +37,7 @@ jobs:
           VENICE_API_KEY: ${{ secrets.VENICE_API_KEY }}
           ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}   # user-level secret on teahubxyz (docs/decisions.md on the spine)
           TIME_TOKEN: ${{ secrets.TIME_TOKEN }}   # repo secret: the `time` bot opens and merges PRs (Gitea denies that to the Actions identity)
+          TIME_SEAT_CLAUDE: ${{ secrets.TIME_SEAT_CLAUDE }}   # the `claude` seat: the reviewer's verdict is a real Gitea review by its own user (#76)
           TIME_TRUSTED: ${{ vars.TIME_TRUSTED }}   # org owners etc.; collaborators are trusted without being listed
           TIME_RUN_IMAGE: node:22-bookworm   # the worker's shell runs in a throwaway container, not next to these secrets
           TIME_MODE: ${{ vars.TIME_MODE }}