feat: add google maps mcp source (#125)

apps/freya-backend/src/google-maps/provider.ts

@@ -0,0 +1,39 @@
+import { GoogleMapsSource, type GoogleMapsSourceOptions } from "@freya/source-google-maps"
+
+import type { FeedSourceProvider } from "../session/feed-source-provider.ts"
+
+export interface GoogleMapsSourceProviderOptions {
+	readonly apiKey: string
+	readonly client?: GoogleMapsSourceOptions["client"]
+}
+
+export class GoogleMapsSourceProvider implements FeedSourceProvider {
+	readonly sourceId = "freya.google-maps"
+
+	private readonly apiKey: string
+	private readonly client: GoogleMapsSourceProviderOptions["client"]
+
+	constructor(options: GoogleMapsSourceProviderOptions) {
+		if (!nonEmptyString(options.apiKey)) {
+			throw new Error("Google Maps MCP API key must be configured")
+		}
+
+		this.apiKey = options.apiKey
+		this.client = options.client
+	}
+
+	async feedSourceForUser(
+		_userId: string,
+		_config: unknown,
+		_credentials: unknown,
+	): Promise<GoogleMapsSource> {
+		return new GoogleMapsSource({
+			apiKey: this.apiKey,
+			client: this.client,
+		})
+	}
+}
+
+function nonEmptyString(value: string): boolean {
+	return typeof value === "string" && value.trim().length > 0
+}