feat(wetter): add weather module with Open-Meteo, DWD alerts, and rain nowcast

New module providing weather data for the DACH region via three sources:
- Open-Meteo (DWD ICON-D2 model) for current conditions and 7-day forecast
- DWD warnings endpoint for severe weather alerts
- Rainbow.ai / Open-Meteo fallback for minute-level rain nowcast

Includes API proxy with in-memory caching, Svelte 5 UI with location
picker, hourly/daily forecast, alert cards, and precipitation bar chart.
Two AI tools (get_weather, get_rain_forecast) enable the companion to
answer weather questions.

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

packages/shared-ai/src/tools/schemas.ts

@@ -854,6 +854,38 @@ export const AI_TOOL_CATALOG: readonly ToolSchema[] = [
 		defaultPolicy: 'auto',
 		parameters: [],
 	},
+
+	// ── Wetter ───────────────────────────────────────────────────
+	{
+		name: 'get_weather',
+		module: 'wetter',
+		description:
+			'Gibt aktuelle Wetterbedingungen und 7-Tage-Vorhersage fuer einen Ort zurueck. Akzeptiert Ortsname oder Koordinaten.',
+		defaultPolicy: 'auto',
+		parameters: [
+			{
+				name: 'location',
+				type: 'string',
+				description: 'Ortsname (z.B. "Berlin") oder "lat,lon" Koordinaten',
+				required: true,
+			},
+		],
+	},
+	{
+		name: 'get_rain_forecast',
+		module: 'wetter',
+		description:
+			'Gibt eine Minuten-Regenprognose (Nowcast) und aktive Wetterwarnungen fuer einen Ort zurueck.',
+		defaultPolicy: 'auto',
+		parameters: [
+			{
+				name: 'location',
+				type: 'string',
+				description: 'Ortsname oder "lat,lon" Koordinaten',
+				required: true,
+			},
+		],
+	},
 ];
 
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