Remove duplicate serverUrl getter and fix gitignore

- Removed duplicate serverUrl getter at line 310
- Fixed .gitignore to only ignore Python lib/ not Flutter lib/
- Build should now work

.gitignore

@@ -18,14 +18,16 @@ __pycache__/
 *$py.class
 *.so
 .Python
-build/
 develop-eggs/
 dist/
 downloads/
 eggs/
 .eggs/
-lib/
-lib64/
+# Ignore Python lib directories but not Flutter's lib/
+/lib/
+/lib64/
+backend/lib/
+backend/lib64/
 parts/
 sdist/
 var/
@@ -34,6 +36,8 @@ wheels/
 .installed.cfg
 *.egg
 MANIFEST
+# Python build/ but keep Flutter build/ unignored separately below
+/build/
 
 # Virtual environments
 venv/

mobile_app/lib/services/api_client.dart

@@ -305,7 +305,4 @@ class ApiClient {
 
   /// Check if authenticated
   bool get isAuthenticated => _token != null;
-
-  /// Get current server URL
-  String get serverUrl => _serverUrl ?? baseUrl;
 }