- Fix return type annotation in SetupRedirectMiddleware.dispatch() to use Response instead of RedirectResponse
- Replace broad 'except Exception' with specific exception types (FileNotFoundError, ValueError, OSError, etc.)
- Rename AppConfig.validate() to validate_config() to avoid shadowing BaseModel.validate()
- Fix ValidationResult.errors field to use List[str] with default_factory
- Add pylint disable comments for intentional broad exception catches during shutdown
- Rename lifespan parameter to _application to indicate unused variable
- Update all callers to use new validate_config() method name
