fix(auth): Update API response parsing to handle nested structure

- Fix 'id_user' key not found error by navigating the correct nested path
- Extract id_user from data.user.applications[0].users[0].id_user
- Add fallback to old structure for backward compatibility
- Prevents authentication failures due to API response format changes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/auth.py

@@ -77,7 +77,13 @@ class AuthHandler:
 
             try:
                 login_data: Dict[str, Any] = response.json()
-                self.user_id = str(login_data["data"]["user"]["id_user"])
+                # Try to find id_user in the nested structure
+                try:
+                    # First try the new structure: data.user.applications[0].users[0].id_user
+                    self.user_id = str(login_data["data"]["user"]["applications"][0]["users"][0]["id_user"])
+                except (KeyError, IndexError, TypeError):
+                    # Fallback to old structure if it exists
+                    self.user_id = str(login_data["data"]["user"]["id_user"])
             except (KeyError, ValueError) as e:
                 logging.error(f"Error during login: {str(e)} - Response: {response.text}")
                 return False