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/static/locales/en.json

@@ -1140,6 +1140,16 @@
     "color_strip.type.candlelight": "Candlelight",
     "color_strip.type.candlelight.desc": "Realistic flickering candle simulation",
     "color_strip.type.candlelight.hint": "Simulates realistic candle flickering across all LEDs with warm tones and organic flicker patterns.",
+    "color_strip.type.weather": "Weather",
+    "color_strip.type.weather.desc": "Weather-reactive ambient colors",
+    "color_strip.type.weather.hint": "Maps real-time weather conditions to ambient LED colors. Requires a Weather Source entity.",
+    "color_strip.weather.source": "Weather Source:",
+    "color_strip.weather.source.hint": "The weather data source to use for ambient colors. Create one in the Weather tab first.",
+    "color_strip.weather.speed": "Animation Speed:",
+    "color_strip.weather.speed.hint": "Speed of the ambient color drift animation. Higher = faster movement.",
+    "color_strip.weather.temperature_influence": "Temperature Influence:",
+    "color_strip.weather.temperature_influence.hint": "How much the current temperature shifts the palette warm/cool. 0 = pure condition colors, 1 = strong shift.",
+    "color_strip.weather.error.no_source": "Please select a weather source",
     "color_strip.candlelight.color": "Base Color:",
     "color_strip.candlelight.color.hint": "The warm base color of the candle flame. Default is a natural warm amber.",
     "color_strip.candlelight.intensity": "Flicker Intensity:",
@@ -1704,6 +1714,35 @@
     "sync_clock.reset_done": "Clock reset to zero",
     "sync_clock.delete.confirm": "Delete this sync clock? Linked sources will lose synchronization and run at default speed.",
     "sync_clock.elapsed": "Elapsed time",
+    "weather_source.group.title": "Weather Sources",
+    "weather_source.add": "Add Weather Source",
+    "weather_source.edit": "Edit Weather Source",
+    "weather_source.name": "Name:",
+    "weather_source.name.placeholder": "My Weather",
+    "weather_source.name.hint": "A descriptive name for this weather data source",
+    "weather_source.provider": "Provider:",
+    "weather_source.provider.hint": "Weather data provider. Open-Meteo is free and requires no API key.",
+    "weather_source.provider.open_meteo.desc": "Free, no API key required",
+    "weather_source.location": "Location:",
+    "weather_source.location.hint": "Your geographic coordinates. Use the auto-detect button or enter manually.",
+    "weather_source.latitude": "Lat:",
+    "weather_source.longitude": "Lon:",
+    "weather_source.use_my_location": "Use my location",
+    "weather_source.update_interval": "Update Interval:",
+    "weather_source.update_interval.hint": "How often to fetch weather data. Lower values give more responsive changes.",
+    "weather_source.description": "Description (optional):",
+    "weather_source.description.placeholder": "Optional description",
+    "weather_source.test": "Test",
+    "weather_source.error.name_required": "Weather source name is required",
+    "weather_source.error.load": "Failed to load weather source",
+    "weather_source.created": "Weather source created",
+    "weather_source.updated": "Weather source updated",
+    "weather_source.deleted": "Weather source deleted",
+    "weather_source.delete.confirm": "Delete this weather source? Linked color strip sources will lose weather data.",
+    "weather_source.geo.success": "Location detected",
+    "weather_source.geo.error": "Geolocation failed",
+    "weather_source.geo.not_supported": "Geolocation is not supported by your browser",
+    "streams.group.weather": "Weather",
     "color_strip.clock": "Sync Clock:",
     "color_strip.clock.hint": "Link to a sync clock to synchronize animation timing across sources. Speed is controlled on the clock.",
     "graph.title": "Graph",
@@ -1814,6 +1853,7 @@
     "section.empty.color_strips": "No color strips yet. Click + to add one.",
     "section.empty.value_sources": "No value sources yet. Click + to add one.",
     "section.empty.sync_clocks": "No sync clocks yet. Click + to add one.",
+    "section.empty.weather_sources": "No weather sources yet. Click + to add one.",
     "section.empty.cspt": "No CSS processing templates yet. Click + to add one.",
     "section.empty.automations": "No automations yet. Click + to add one.",
     "section.empty.scenes": "No scene presets yet. Click + to add one.",