update_log_5.0.15.md

# WorkersPanel 5.0.15

- Bumps the branding-safe package to its own version number instead of reusing 5.0.14.
- Protects `assets/images/` from future updater copy/delete operations so installed logos and favicons survive updates.
- Adds favicon upload beside logo upload in the installer.
- Saves `favicon_path` and resolves favicon/logo from installed system settings first.
- Falls back to the uploaded logo as favicon when no favicon is set.
- Keeps the 5.0.14 Calendar and Live Map permission changes.