feat: agregar endpoint /autocomplete en admin Next.js

Proxy a Google Places Autocomplete API:
- Lee la API key de /settings/maps-key del backend
- Acepta params: input, location
- Devuelve { results: [{ formatted_address, place_id }] }
- Headers CORS para permitir acceso desde app.prosapp.co

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

admin/src/app/autocomplete/route.ts

@@ -0,0 +1,83 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+const API_BASE = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3000/api/v1';
+
+// Cache the Maps API key in memory (refreshes every 5 min)
+let cachedKey: string | null = null;
+let cacheTime = 0;
+
+async function getMapsKey(): Promise<string | null> {
+  const now = Date.now();
+  if (cachedKey && now - cacheTime < 5 * 60 * 1000) return cachedKey;
+  try {
+    const res = await fetch(`${API_BASE}/settings/maps-key`, { cache: 'no-store' });
+    if (!res.ok) return null;
+    const data = await res.json();
+    cachedKey = data.api_key || null;
+    cacheTime = now;
+    return cachedKey;
+  } catch {
+    return null;
+  }
+}
+
+export async function GET(req: NextRequest) {
+  const { searchParams } = req.nextUrl;
+  const input = searchParams.get('input')?.trim();
+  const location = searchParams.get('location') ?? '';
+
+  if (!input || input.length < 2) {
+    return NextResponse.json({ results: [] });
+  }
+
+  const apiKey = await getMapsKey();
+  if (!apiKey) {
+    return NextResponse.json(
+      { error: 'Google Maps API key not configured' },
+      { status: 503 },
+    );
+  }
+
+  // Use Places Autocomplete for typed suggestions
+  const placesUrl = new URL('https://maps.googleapis.com/maps/api/place/autocomplete/json');
+  placesUrl.searchParams.set('input', input);
+  placesUrl.searchParams.set('key', apiKey);
+  placesUrl.searchParams.set('language', 'es');
+  placesUrl.searchParams.set('types', 'address');
+  if (location) placesUrl.searchParams.set('location', location);
+  if (location) placesUrl.searchParams.set('radius', '50000');
+
+  try {
+    const res = await fetch(placesUrl.toString(), { cache: 'no-store' });
+    const data = await res.json();
+
+    if (data.status !== 'OK' && data.status !== 'ZERO_RESULTS') {
+      return NextResponse.json({ results: [] });
+    }
+
+    // Normalize predictions → results with formatted_address for Flutter compatibility
+    const results = (data.predictions ?? []).map((p: any) => ({
+      formatted_address: p.description,
+      place_id: p.place_id,
+    }));
+
+    return NextResponse.json({ results }, {
+      headers: {
+        'Access-Control-Allow-Origin': '*',
+        'Access-Control-Allow-Methods': 'GET',
+      },
+    });
+  } catch {
+    return NextResponse.json({ results: [] });
+  }
+}
+
+export async function OPTIONS() {
+  return new NextResponse(null, {
+    headers: {
+      'Access-Control-Allow-Origin': '*',
+      'Access-Control-Allow-Methods': 'GET, OPTIONS',
+      'Access-Control-Allow-Headers': 'Content-Type',
+    },
+  });
+}