ORJSONResponse and UJSONResponse deprecated in favor of Pydantic serialization

FastAPI 0.131.0 deprecates ORJSONResponse and UJSONResponse. With Pydantic's Rust-based JSON serializer in 0.130.0 providing superior performance, these alternative response classes are no longer needed and will be removed in a future version.

Search codebase for ORJSONResponse and UJSONResponse imports and usage. Replace with standard JSONResponse or rely on default response handling with Pydantic models. Benchmark to confirm Pydantic serializer meets performance requirements before removing custom response classes.