Miscellaneous fixes (0.18 beta) (#23736)

* Catch faces that become empty after cropping

* don't drop batched camera add/remove config updates

TrackedObjectProcessor drained all pending camera config updates at once but handled them in a mutually exclusive if/elif on enabled/add/remove, so only one topic was processed per drain. When an add arrived in the same batch as an enabled update, the add was skipped and the new camera never got a camera state. Adding a camera reliably produced that batch: config_set now re-applies runtime overrides, which republishes an enabled update for every previously toggled camera immediately before the add, in the same request. The dashboard and camera capture still saw the camera (the maintainer does not subscribe to enabled, so it got a clean add-only batch), but object_processing did not, and disabling the camera then crashed with a KeyError on the unguarded camera_states lookup.

Handle add and remove independently instead of as exclusive branches so a batched add is no longer dropped, and guard the remove lookup so a missing state is skipped rather than raising. Drop the enabled branch entirely: it only ever set prev_enabled when it was None, but prev_enabled is seeded to a bool at camera state creation and is never None (mypy flags the body as unreachable), and the actual enable/disable transition is already driven by the disabled-state loop from config.enabled.

* Don't stay on motion search page when user cancels flow

* fix notification test button being blocked by websocket auth

* fix overflowing model names in settings genai widget

* add note about auth debugging

---------

Co-authored-by: Nicolas Mowen <nickmowen213@gmail.com>

docs/docs/configuration/authentication.md

@@ -262,6 +262,19 @@ In this example:
 
 - Admin precedence: if the `admin` mapping matches, Frigate resolves the session to `admin` to avoid accidental downgrade when a user belongs to multiple groups (for example both `admin` and `viewer` groups).
 
+:::note
+
+If a user isn't getting the role you expect, enable debug logging to see exactly what headers Frigate is receiving from your proxy:
+
+```yaml
+logger:
+  default: info
+  logs:
+    frigate.api.auth: debug
+```
+
+:::
+
 #### Port Considerations
 
 **Authenticated Port (8971)**