feat: HA light output targets — cast LED colors to Home Assistant lights

New output target type `ha_light` that sends averaged LED colors to HA
light entities via WebSocket service calls (light.turn_on/turn_off):

Backend:
- HARuntime.call_service(): fire-and-forget WS service calls
- HALightOutputTarget: data model with light mappings, update rate, transition
- HALightTargetProcessor: processing loop with delta detection, rate limiting
- ProcessorManager.add_ha_light_target(): registration
- API schemas/routes updated for ha_light target type

Frontend:
- HA Light Targets section in Targets tab tree nav
- Modal editor: HA source picker, CSS source picker, light entity mappings
- Target cards with start/stop/clone/edit actions
- i18n keys for all new UI strings

server/src/wled_controller/api/routes/output_targets.py

@@ -25,6 +25,11 @@ from wled_controller.storage.key_colors_output_target import (
     KeyColorsSettings,
     KeyColorsOutputTarget,
 )
+from wled_controller.storage.ha_light_output_target import (
+    HALightMapping,
+    HALightOutputTarget,
+)
+from wled_controller.api.schemas.output_targets import HALightMappingSchema
 from wled_controller.storage.output_target_store import OutputTargetStore
 from wled_controller.utils import get_logger
 from wled_controller.storage.base_store import EntityNotFoundError
@@ -76,7 +81,6 @@ def _target_to_response(target) -> OutputTargetResponse:
             protocol=target.protocol,
             description=target.description,
             tags=target.tags,
-
             created_at=target.created_at,
             updated_at=target.updated_at,
         )
@@ -89,7 +93,31 @@ def _target_to_response(target) -> OutputTargetResponse:
             key_colors_settings=_kc_settings_to_schema(target.settings),
             description=target.description,
             tags=target.tags,
-
+            created_at=target.created_at,
+            updated_at=target.updated_at,
+        )
+    elif isinstance(target, HALightOutputTarget):
+        return OutputTargetResponse(
+            id=target.id,
+            name=target.name,
+            target_type=target.target_type,
+            ha_source_id=target.ha_source_id,
+            color_strip_source_id=target.color_strip_source_id,
+            ha_light_mappings=[
+                HALightMappingSchema(
+                    entity_id=m.entity_id,
+                    led_start=m.led_start,
+                    led_end=m.led_end,
+                    brightness_scale=m.brightness_scale,
+                )
+                for m in target.light_mappings
+            ],
+            update_rate=target.update_rate,
+            ha_transition=target.transition,
+            color_tolerance=target.color_tolerance,
+            min_brightness_threshold=target.min_brightness_threshold,
+            description=target.description,
+            tags=target.tags,
             created_at=target.created_at,
             updated_at=target.updated_at,
         )
@@ -100,7 +128,6 @@ def _target_to_response(target) -> OutputTargetResponse:
             target_type=target.target_type,
             description=target.description,
             tags=target.tags,
-
             created_at=target.created_at,
             updated_at=target.updated_at,
         )
@@ -108,7 +135,10 @@ def _target_to_response(target) -> OutputTargetResponse:
 
 # ===== CRUD ENDPOINTS =====
 
-@router.post("/api/v1/output-targets", response_model=OutputTargetResponse, tags=["Targets"], status_code=201)
+
+@router.post(
+    "/api/v1/output-targets", response_model=OutputTargetResponse, tags=["Targets"], status_code=201
+)
 async def create_target(
     data: OutputTargetCreate,
     _auth: AuthRequired,
@@ -125,7 +155,22 @@ async def create_target(
             except ValueError:
                 raise HTTPException(status_code=422, detail=f"Device {data.device_id} not found")
 
-        kc_settings = _kc_schema_to_settings(data.key_colors_settings) if data.key_colors_settings else None
+        kc_settings = (
+            _kc_schema_to_settings(data.key_colors_settings) if data.key_colors_settings else None
+        )
+        ha_mappings = (
+            [
+                HALightMapping(
+                    entity_id=m.entity_id,
+                    led_start=m.led_start,
+                    led_end=m.led_end,
+                    brightness_scale=m.brightness_scale,
+                )
+                for m in data.ha_light_mappings
+            ]
+            if data.ha_light_mappings
+            else None
+        )
 
         # Create in store
         target = target_store.create_target(
@@ -144,6 +189,11 @@ async def create_target(
             key_colors_settings=kc_settings,
             description=data.description,
             tags=data.tags,
+            ha_source_id=data.ha_source_id,
+            ha_light_mappings=ha_mappings,
+            update_rate=data.update_rate,
+            transition=data.transition,
+            color_tolerance=data.color_tolerance,
         )
 
         # Register in processor manager
@@ -196,7 +246,9 @@ async def batch_target_metrics(
     return {"metrics": manager.get_all_target_metrics()}
 
 
-@router.get("/api/v1/output-targets/{target_id}", response_model=OutputTargetResponse, tags=["Targets"])
+@router.get(
+    "/api/v1/output-targets/{target_id}", response_model=OutputTargetResponse, tags=["Targets"]
+)
 async def get_target(
     target_id: str,
     _auth: AuthRequired,
@@ -210,7 +262,9 @@ async def get_target(
         raise HTTPException(status_code=404, detail=str(e))
 
 
-@router.put("/api/v1/output-targets/{target_id}", response_model=OutputTargetResponse, tags=["Targets"])
+@router.put(
+    "/api/v1/output-targets/{target_id}", response_model=OutputTargetResponse, tags=["Targets"]
+)
 async def update_target(
     target_id: str,
     data: OutputTargetUpdate,
@@ -246,7 +300,9 @@ async def update_target(
                     smoothing=incoming.get("smoothing", ex.smoothing),
                     pattern_template_id=incoming.get("pattern_template_id", ex.pattern_template_id),
                     brightness=incoming.get("brightness", ex.brightness),
-                    brightness_value_source_id=incoming.get("brightness_value_source_id", ex.brightness_value_source_id),
+                    brightness_value_source_id=incoming.get(
+                        "brightness_value_source_id", ex.brightness_value_source_id
+                    ),
                 )
                 kc_settings = _kc_schema_to_settings(merged)
             else:
@@ -282,14 +338,18 @@ async def update_target(
             await asyncio.to_thread(
                 target.sync_with_manager,
                 manager,
-                settings_changed=(data.fps is not None or
-                                  data.keepalive_interval is not None or
-                                  data.state_check_interval is not None or
-                                  data.min_brightness_threshold is not None or
-                                  data.adaptive_fps is not None or
-                                  data.key_colors_settings is not None),
+                settings_changed=(
+                    data.fps is not None
+                    or data.keepalive_interval is not None
+                    or data.state_check_interval is not None
+                    or data.min_brightness_threshold is not None
+                    or data.adaptive_fps is not None
+                    or data.key_colors_settings is not None
+                ),
                 css_changed=data.color_strip_source_id is not None,
-                brightness_vs_changed=(data.brightness_value_source_id is not None or kc_brightness_vs_changed),
+                brightness_vs_changed=(
+                    data.brightness_value_source_id is not None or kc_brightness_vs_changed
+                ),
             )
         except ValueError as e:
             logger.debug("Processor config update skipped for target %s: %s", target_id, e)