fix: prevent failed containers from showing as running on dashboard

- Add final get_container_status check in start_tool_instance before
  writing status=running; mark as error and return logs if container stopped
- Treat restarting as error in HealthMonitor when DB status was already
  running, so crash loops are surfaced instead of preserved
- Disable auto-restart (restart: unless-stopped -> restart: no) for tool
  instances in manifest compiler, legacy dockerfile path, and built-in seeds

Quality gates:
- pytest tests/unit: 210 passed
- ruff: clean on changed files
- mypy: clean on changed files

apps/api/src/services/build/manifest_compiler.py

@@ -411,7 +411,7 @@ def compile_compose(manifest: dict, variables: dict[str, Any]) -> str:
     service: dict[str, Any] = {
         "image": variables["IMAGE_TAG"],
         "container_name": variables["INSTANCE_NAME"],
-        "restart": "unless-stopped",
+        "restart": "no",
     }
 
     # Terminal-specific fields