Add winter mode to front-end integration under lab preview feature (home-assistant#157181)

Author: piitaya

homeassistant/components/frontend/manifest.json

@@ -19,6 +19,9 @@
   ],
   "documentation": "https://www.home-assistant.io/integrations/frontend",
   "integration_type": "system",
+  "preview_features": {
+    "winter_mode": {}
+  },
   "quality_scale": "internal",
   "requirements": ["home-assistant-frontend==20251105.1"]
 }

homeassistant/components/frontend/strings.json

@@ -1,4 +1,12 @@
 {
+  "preview_features": {
+    "winter_mode": {
+      "description": "Adds falling snowflakes on your screen. Get your home ready for winter! ❄️",
+      "disable_confirmation": "Snowflakes will no longer fall on your screen. You can re-enable this at any time in labs settings.",
+      "enable_confirmation": "Snowflakes will start falling on your screen. You can turn this off at any time in labs settings.",
+      "name": "Winter mode"
+    }
+  },
   "selector": {
     "mode": {
       "options": {