- feat(cos): add cos_upload.py for direct file upload without browser
- implements COS V1 signature algorithm with temporary credentials
- upload_image() pipeline: get_upload_info → sign → PUT to COS
- feat(api): auto-load cookies from file when cookies arg is omitted
- both Hunyuan3DAPI and Hunyuan3DAPIComplete now fall back to
~/.config/hunyuan3dweb/cookies.txt automatically
- fix(login): strengthen login-state detection using both URL and DOM
- checks "login" not in page.url AND no login button on page
- docs: update README / README_CN with COS upload examples
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>