- **TestSetup.cs**
- Updated `CreateTestConfig` method to initialize `Config` with required properties using object initializer syntax.
- **ProxyIntegrationTests.cs**
- Added null checks for `mockServer.Urls` before accessing it to prevent potential null reference exceptions.
- Improved error handling for mock server URL access.
- **VRChatAuthenticationTests.cs**
- Added null checks for `mockServer.Urls` before accessing it to prevent potential null reference exceptions.
- Enhanced the mock server setup to include null checks for request body content.
- **Config.cs**
- Added the `required` modifier to non-nullable properties in `ConfigAccount` and `iConfig` classes.
- Updated the `Load` method to initialize the `Config` instance with required properties using object initializer syntax.
- **Program.cs**
- Added a null check for `result.CloseStatus` in WebSocket handling to prevent potential null reference exceptions.
