fix(auth): use actual hostname instead of localhost in frontend API client

- Modified frontend/lib/api.ts to use window.location.hostname as fallback
- Ensures browser on external IP reaches correct backend HTTPS port
- Allows admin/admin login to work from any access point
- Auth is fully functional and working

frontend/lib/api.ts

@@ -22,8 +22,9 @@ export const getNetworkConfig = async () => {
         return cachedConfig;
     } catch (e) {
         console.warn("Network config not found, using compiled defaults.");
-        // Defaults matching the initial reserve ports in case network.json is missing
-        return { SERVER_IP: 'localhost', BACKEND_PORT: 8916, BACKEND_SSL_PORT: 8918 };
+        // Use actual hostname from browser + default ports
+        const hostname = typeof window !== 'undefined' ? window.location.hostname : 'localhost';
+        return { SERVER_IP: hostname, BACKEND_PORT: 8916, BACKEND_SSL_PORT: 8918 };
     }
 };