Introduced utils/http/http_exceptions.py with common HTTP exception helpers for FastAPI. Updated main.py to use a global exception handler that logs and hides internal errors. Refined models/README.md to document new models and relationships, including PhysicalFile and UploadSession, and updated DTO and enum documentation. Simplified ThemeResponse in models/color.py. Improved models/download.py with type annotations, index changes, and import optimizations. Fixed a parameter type in clean.py.
Co-Authored-By: 砂糖橘 <54745033+Foxerine@users.noreply.github.com>
