fix: add PYTHONPATH environment variable and ensure src is importable in app.py

fix: update Dockerfile dependencies, remove audio processing, and replace models

feat: enhance model capabilities and update dependencies

Use CPU-only PyTorch wheels in Docker build for HF Space stability

fix(space): set PYTHONPATH and prefer Gemini 3.1 with 2.5 fallback

fix(docker): replace removed libgl1-mesa-glx with libgl1

Initial commit