feat(agent): survive + auto-recover when curator is unreachable

For redeploying curator while away with nobody to restart the agent:

- _process now distinguishes a TRANSPORT error (curator down/redeploying, 5xx,
  401/403/408/409/429, or our lease reclaimed mid-flight) from a genuine job
  fault. On a transport error it hands the job back (best effort) and signals
  the loop to back off — instead of calling fail(), which would burn the job's
  server-side attempt budget (MAX_ATTEMPTS=3) and permanently error good jobs
  across a redeploy. Job-specific 4xx (404 image gone) still fail so they don't
  re-lease forever.
- lease loop retries with capped exponential backoff (poll_idle → 60s) and
  resets on the first successful lease, so a long outage is gentle and recovery
  is automatic within ≤60s of curator returning. Sleeps are interruptible so
  Stop / pool-shrink stays responsive.
- AUTO_START env (default on in compose) resumes the worker on container start,
  so a host reboot / crash-restart (restart: unless-stopped) self-heals with
  nobody at the desktop.
- control UI shows a "waited out" counter + an "curator unreachable, holding
  work" banner so the recovering state reads as recovery, not failure.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ttrj5P7upUTueSfoJcxEqa

agent/docker-compose.yml

@@ -10,6 +10,13 @@
 #   4. Open http://localhost:8770 → Start. Pause/Stop hands the GPU back.
 #      docker compose down       to stop the container entirely.
 #
+# Surviving a curator redeploy (you're away, can't touch the agent):
+#   - A running agent rides out curator being unreachable on its own — it retries
+#     leasing with capped backoff and resumes when the server is back. In-flight
+#     work is handed back (not failed), so a redeploy never poisons good jobs.
+#   - AUTO_START=1 (below) also resumes the worker if the AGENT container itself
+#     restarts (host reboot / crash via `restart: unless-stopped`) — no click.
+#
 # Needs the NVIDIA Container Toolkit installed on the host for --gpus.
 
 services:
@@ -24,6 +31,12 @@ services:
       CCIP_MODEL: ${CCIP_MODEL:-}
       DETECTOR_LEVEL: ${DETECTOR_LEVEL:-m}
       BATCH_SIZE: ${BATCH_SIZE:-4}
+      # Resume the worker automatically on container start (survive a reboot /
+      # crash-restart while you're away). Set to 0 to require a manual Start.
+      AUTO_START: ${AUTO_START:-1}
+      # Crop embedder (SigLIP concept bag): float16 keeps VRAM low on a shared
+      # desktop GPU; the model itself is announced by the server.
+      SIGLIP_DTYPE: ${SIGLIP_DTYPE:-float16}
     volumes:
       # Persist the downloaded ONNX models so restarts are fast.
       - fc-agent-models:/models