feat: make mode creation preview-only and cache-safe

src/cognitive_agent/application/seat_service.py

@@ -2150,6 +2150,13 @@ class SeatDemoService(ModeScheduleServiceMixin):
         vehicle_profile = self.vehicle_profiles.get(vehicle_id)
         control_plane_request = self.is_mode_profile_configuration_request(utterance)
         if control_plane_request:
+            # Mode creation is a configuration workflow, never a vehicle
+            # execution request. Enforce this at the public preview boundary
+            # even when a browser is currently set to hardware mode.
+            if parse_mode_profile_create(utterance) is not None:
+                execution_mode = "dry_run"
+                approval_token = None
+                hardware_client_id = None
             result = self.process(
                 utterance,
                 provider=provider,