feat: localization service and frontend integration

- Add localization-service microservice (locale resolution, translations)
- Add frontend API routes /api/locale and /api/translations/[locale]
- Add LocalizationProvider and localization context
- Integrate localization into layout, EmptyChat, MessageInput components
- Update MICROSERVICES.md architecture docs
- Add localization-service to workspaces

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/localization-service/src/lib/geoClient.ts

@@ -0,0 +1,31 @@
+import type { GeoDeviceContext } from '../types.js';
+
+const GEO_DEVICE_URL =
+  process.env.GEO_DEVICE_SERVICE_URL ?? 'http://localhost:4002';
+
+export async function fetchGeoContext(
+  headers: Record<string, string>,
+  body?: unknown,
+): Promise<GeoDeviceContext | null> {
+  try {
+    const url = `${GEO_DEVICE_URL}/api/context`;
+    const options: RequestInit = {
+      method: body ? 'POST' : 'GET',
+      headers: {
+        'Content-Type': 'application/json',
+        'user-agent': headers['user-agent'] ?? '',
+        'accept-language': headers['accept-language'] ?? '',
+        'x-forwarded-for': headers['x-forwarded-for'] ?? '',
+        'x-real-ip': headers['x-real-ip'] ?? '',
+      },
+    };
+    if (body) {
+      options.body = JSON.stringify(body);
+    }
+    const res = await fetch(url, options);
+    if (!res.ok) return null;
+    return (await res.json()) as GeoDeviceContext;
+  } catch {
+    return null;
+  }
+}