Fix Python 3.9 compatibility - replace union syntax | with Union

Fix pre-commit configuration and resolve all linting issues

Apply code formatting and fix compatibility issues

Fix Hugging Face cache path configuration for Spaces

Remove all FLUX references and use only SDXL models

Use SDXL-Turbo on HF Spaces to avoid permission errors

Auto-disable FLUX on Hugging Face Spaces to prevent access errors

Make it run locally with new sdxl-base model

Switch primary model from FLUX to SDXL for better reliability

Add modern Python development toolchain with Ruff, MyPy, and pre-commit

Migrate entire codebase from SDXL-Turbo to FLUX.1-schnell

Refactoring again for imports and fixed error

Refactor the app to be more modular