HA integration: fix reload loop, parallel device fetch, WS guards, translations

- Fix indentation bug causing scenes device to not register
- Use nonlocal tracking to prevent infinite reload loops on target/scene changes
- Guard WS start/stop to avoid redundant connections
- Parallel device brightness fetching via asyncio.gather
- Route set_leds service to correct coordinator by source ID
- Remove stale pattern cache, reuse single timeout object
- Fix translations structure for light/select entities
- Unregister service when last config entry unloaded

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

custom_components/wled_screen_controller/light.py

@@ -63,9 +63,13 @@ class ApiInputLight(CoordinatorEntity, LightEntity):
         self._entry_id = entry_id
         self._attr_unique_id = f"{self._source_id}_light"
 
-        # Local state — not derived from coordinator data
-        self._is_on: bool = False
-        self._rgb_color: tuple[int, int, int] = (255, 255, 255)
+        # Restore state from fallback_color
+        fallback = self._get_fallback_color()
+        is_off = fallback == [0, 0, 0]
+        self._is_on: bool = not is_off
+        self._rgb_color: tuple[int, int, int] = (
+            (255, 255, 255) if is_off else tuple(fallback)  # type: ignore[arg-type]
+        )
         self._brightness: int = 255
 
     @property