feat: add weather source entity and weather-reactive CSS source type

New standalone WeatherSource entity with pluggable provider architecture
(Open-Meteo v1, free, no API key). Full CRUD, test endpoint, browser
geolocation, IconSelect provider picker, CardSection with test/clone/edit.

WeatherColorStripStream maps WMO weather codes to ambient color palettes
with temperature hue shifting and thunderstorm flash effects. Ref-counted
WeatherManager polls API and caches data per source.

CSS editor integration: weather type with EntitySelect source picker,
speed and temperature influence sliders. Backup/restore support.

i18n for en/ru/zh.

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

@@ -0,0 +1,157 @@
+"""Weather source routes: CRUD + test endpoint."""
+
+from fastapi import APIRouter, Depends, HTTPException
+
+from wled_controller.api.auth import AuthRequired
+from wled_controller.api.dependencies import (
+    fire_entity_event,
+    get_weather_manager,
+    get_weather_source_store,
+)
+from wled_controller.api.schemas.weather_sources import (
+    WeatherSourceCreate,
+    WeatherSourceListResponse,
+    WeatherSourceResponse,
+    WeatherSourceUpdate,
+    WeatherTestResponse,
+)
+from wled_controller.core.weather.weather_manager import WeatherManager
+from wled_controller.core.weather.weather_provider import WMO_CONDITION_NAMES
+from wled_controller.storage.base_store import EntityNotFoundError
+from wled_controller.storage.weather_source import WeatherSource
+from wled_controller.storage.weather_source_store import WeatherSourceStore
+from wled_controller.utils import get_logger
+
+logger = get_logger(__name__)
+
+router = APIRouter()
+
+
+def _to_response(source: WeatherSource) -> WeatherSourceResponse:
+    d = source.to_dict()
+    return WeatherSourceResponse(
+        id=d["id"],
+        name=d["name"],
+        provider=d["provider"],
+        provider_config=d.get("provider_config", {}),
+        latitude=d["latitude"],
+        longitude=d["longitude"],
+        update_interval=d["update_interval"],
+        description=d.get("description"),
+        tags=d.get("tags", []),
+        created_at=source.created_at,
+        updated_at=source.updated_at,
+    )
+
+
+@router.get("/api/v1/weather-sources", response_model=WeatherSourceListResponse, tags=["Weather Sources"])
+async def list_weather_sources(
+    _auth: AuthRequired,
+    store: WeatherSourceStore = Depends(get_weather_source_store),
+):
+    sources = store.get_all_sources()
+    return WeatherSourceListResponse(
+        sources=[_to_response(s) for s in sources],
+        count=len(sources),
+    )
+
+
+@router.post("/api/v1/weather-sources", response_model=WeatherSourceResponse, status_code=201, tags=["Weather Sources"])
+async def create_weather_source(
+    data: WeatherSourceCreate,
+    _auth: AuthRequired,
+    store: WeatherSourceStore = Depends(get_weather_source_store),
+):
+    try:
+        source = store.create_source(
+            name=data.name,
+            provider=data.provider,
+            provider_config=data.provider_config,
+            latitude=data.latitude,
+            longitude=data.longitude,
+            update_interval=data.update_interval,
+            description=data.description,
+            tags=data.tags,
+        )
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    fire_entity_event("weather_source", "created", source.id)
+    return _to_response(source)
+
+
+@router.get("/api/v1/weather-sources/{source_id}", response_model=WeatherSourceResponse, tags=["Weather Sources"])
+async def get_weather_source(
+    source_id: str,
+    _auth: AuthRequired,
+    store: WeatherSourceStore = Depends(get_weather_source_store),
+):
+    try:
+        return _to_response(store.get_source(source_id))
+    except EntityNotFoundError:
+        raise HTTPException(status_code=404, detail=f"Weather source {source_id} not found")
+
+
+@router.put("/api/v1/weather-sources/{source_id}", response_model=WeatherSourceResponse, tags=["Weather Sources"])
+async def update_weather_source(
+    source_id: str,
+    data: WeatherSourceUpdate,
+    _auth: AuthRequired,
+    store: WeatherSourceStore = Depends(get_weather_source_store),
+    manager: WeatherManager = Depends(get_weather_manager),
+):
+    try:
+        source = store.update_source(
+            source_id,
+            name=data.name,
+            provider=data.provider,
+            provider_config=data.provider_config,
+            latitude=data.latitude,
+            longitude=data.longitude,
+            update_interval=data.update_interval,
+            description=data.description,
+            tags=data.tags,
+        )
+    except EntityNotFoundError:
+        raise HTTPException(status_code=404, detail=f"Weather source {source_id} not found")
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    manager.update_source(source_id)
+    fire_entity_event("weather_source", "updated", source.id)
+    return _to_response(source)
+
+
+@router.delete("/api/v1/weather-sources/{source_id}", status_code=204, tags=["Weather Sources"])
+async def delete_weather_source(
+    source_id: str,
+    _auth: AuthRequired,
+    store: WeatherSourceStore = Depends(get_weather_source_store),
+):
+    try:
+        store.delete_source(source_id)
+    except EntityNotFoundError:
+        raise HTTPException(status_code=404, detail=f"Weather source {source_id} not found")
+    fire_entity_event("weather_source", "deleted", source_id)
+
+
+@router.post("/api/v1/weather-sources/{source_id}/test", response_model=WeatherTestResponse, tags=["Weather Sources"])
+async def test_weather_source(
+    source_id: str,
+    _auth: AuthRequired,
+    store: WeatherSourceStore = Depends(get_weather_source_store),
+    manager: WeatherManager = Depends(get_weather_manager),
+):
+    """Force-fetch current weather and return the result."""
+    try:
+        store.get_source(source_id)  # validate exists
+    except EntityNotFoundError:
+        raise HTTPException(status_code=404, detail=f"Weather source {source_id} not found")
+
+    data = manager.fetch_now(source_id)
+    condition = WMO_CONDITION_NAMES.get(data.code, f"Unknown ({data.code})")
+    return WeatherTestResponse(
+        code=data.code,
+        condition=condition,
+        temperature=data.temperature,
+        wind_speed=data.wind_speed,
+        cloud_cover=data.cloud_cover,
+    )