Add free workflow assets and update README to link and showcase them. Embedded SDXL and Flux free workflow links and images (assets/sdxlfree.png, assets/fluxfree.png) in README.md. Bump package version in pyproject.toml from 1.8.7 to 1.8.8.
Relocated maxedout_icon.png from web/assets to the root assets directory to improve asset organization.