feat: serialize public hardware execution

src/cognitive_agent/application/seat_service.py

@@ -61,6 +61,7 @@ from cognitive_agent.infrastructure.llm.openai_responses import (  # noqa: E402
 )
 from cognitive_agent.infrastructure.can.hardware import (  # noqa: E402
     HardwareSafetyError,
+    PHYSICAL_BENCH_COORDINATOR,
     SeatHardwareSettings,
 )
 from cognitive_agent.runtime.contracts import ContractValidator  # noqa: E402
@@ -138,6 +139,7 @@ class SeatDemoService:
             repository_root / "platforms" / "t2g_seat_bench" / "calibration" / "seat.yaml",
         )
         self.hardware_settings = SeatHardwareSettings.from_env(repository_root)
+        self.hardware_execution = PHYSICAL_BENCH_COORDINATOR
         # Shared by the short-lived hardware executor instances. A process must
         # establish a fresh physical four-axis reference before trusting stored
         # Hall counts, and a firmware replacement invalidates it again.
@@ -177,6 +179,8 @@ class SeatDemoService:
             runtime.runtime_info() for runtime in self.domain_runtimes.values()
         ]
         default_vehicle = self.vehicle_profiles.default()
+        hardware_info = self.hardware_settings.public_info()
+        hardware_info.update(self.hardware_execution.public_info())
         return {
             "service": "cabin-cognitive-orchestrator",
             "domain": "cabin",
@@ -184,7 +188,7 @@ class SeatDemoService:
             "execution_mode": "dry_run",
             "execution_modes": ["dry_run", "simulated_hardware", "hardware"],
             "hardware_execution_allowed": self.hardware_settings.configured,
-            "hardware": self.hardware_settings.public_info(),
+            "hardware": hardware_info,
             "seat_position_memory_synchronized": bool(
                 self._seat_position_memory_state.get("synchronized", False)
             ),
@@ -243,6 +247,16 @@ class SeatDemoService:
         self,
         conversation_id: str,
         vehicle_id: str | None = None,
+    ) -> dict[str, Any]:
+        """Read the bench only when no physical execution currently owns it."""
+
+        with self.hardware_execution.reserve():
+            return self._synchronize_hardware_state_once(conversation_id, vehicle_id)
+
+    def _synchronize_hardware_state_once(
+        self,
+        conversation_id: str,
+        vehicle_id: str | None = None,
     ) -> dict[str, Any]:
         """Read the bench and project it into the current passenger conversation."""
 
@@ -308,6 +322,37 @@ class SeatDemoService:
         approval_token: str | None = None,
         vehicle_id: str | None = None,
         simulation_fault: str = "normal",
+    ) -> dict[str, Any]:
+        if execution_mode != "hardware":
+            return self._process_once(
+                utterance,
+                provider,
+                conversation_id,
+                execution_mode,
+                approval_token,
+                vehicle_id,
+                simulation_fault,
+            )
+        with self.hardware_execution.reserve():
+            return self._process_once(
+                utterance,
+                provider,
+                conversation_id,
+                execution_mode,
+                approval_token,
+                vehicle_id,
+                simulation_fault,
+            )
+
+    def _process_once(
+        self,
+        utterance: str,
+        provider: str = "auto",
+        conversation_id: str | None = None,
+        execution_mode: str = "dry_run",
+        approval_token: str | None = None,
+        vehicle_id: str | None = None,
+        simulation_fault: str = "normal",
     ) -> dict[str, Any]:
         utterance = utterance.strip()
         if not utterance: