Fix persisted runtime camera toggles (#23734)

* preserve runtime camera toggles across config saves

Runtime toggles (camera on/off, detect, recordings, snapshots, audio) mutate the in-memory config and persist an override to .runtime_state.json. /api/config/set re-parses yaml into a fresh FrigateConfig and swaps it in, re-applying the yaml and profile layers but dropping the runtime layer, so a camera turned off from the dashboard came back on when an unrelated camera was saved. The workers were never notified, so it only appeared to come back: the UI streamed go2rtc while ffmpeg stayed stopped.

Extract the startup replay into Dispatcher.apply_runtime_state() and call it from config_set after the swap, re-layering the overrides and republishing them so workers and the UI reconverge.

Remove the broad clear_runtime_state() from ProfileManager.update_config, which is only ever reached from config_set: with a profile active, every save wiped every camera's overrides from disk. The broad wipe stays in activate_profile, where a real profile switch does invalidate the steady state. Saves still clear the keys they rewrote via clear_runtime_state_for_yaml_keys, so yaml wins where the two disagree.

* sync runtime config on camera delete and prune its overrides

Deleting a camera re-parsed yaml into a fresh FrigateConfig but only rebound app.frigate_config and genai_manager, never dispatcher.config (nor profile_manager, stats_emitter, or the runtime overrides). The API and the dispatcher then drifted onto different config objects until the next config save re-synced them, so the API reported surviving cameras with their yaml enabled state while the dispatcher still acted on their real runtime state.

Extract the config swap that config_set already does into a shared swap_runtime_config helper and call it from both sites, so every collaborator is rebound and the surviving cameras' runtime toggles are re-layered. Also drop the deleted camera's persisted overrides via a new clear_camera so a camera later added under the same name does not inherit them.

frigate/comms/runtime_state.py

@@ -96,6 +96,25 @@ class RuntimeStatePersistence:
         except OSError:
             logger.exception("Failed to clear runtime state")
 
+    def clear_camera(self, camera: str) -> None:
+        """Drop every stored override for a single camera.
+
+        Called when a camera is deleted so a camera later added under the same
+        name does not inherit the removed camera's stale toggles.
+        """
+        try:
+            with FileLock(self._lock_path, timeout=self._lock_timeout):
+                data = self._read_locked()
+                cameras = data.get("cameras")
+                if not isinstance(cameras, dict) or camera not in cameras:
+                    return
+                del cameras[camera]
+                self._write_locked(data)
+        except Timeout:
+            logger.error("Timed out clearing runtime state for camera")
+        except OSError:
+            logger.exception("Failed to clear runtime state for camera")
+
     def clear_for_yaml_keys(self, dotted_keys: Iterable[str]) -> None:
         """Remove stored entries whose YAML key was just rewritten.