[D3SOX]

Summary

• advertise OpenTubeX gamepad support in AppStream and allow Flatpak input-device access
• refresh the AppStream description from the main project README, use the structured developer field, add branding and keywords, update OARS to 1.1, and point translations at the current Weblate instance
• pin screenshots and the icon to the latest stable OpenTubeX release instead of the development branch
• update the release workflow to keep those media assets pinned to the latest stable tag and refresh the icon checksum
• filter OpenTubeX source checkers to non-prerelease, non-draft releases
• clean up the desktop entry categories, generic name, comments, and keywords
• add metadata validation on pull requests and before release builds

Release-note metadata and existing D-Bus permissions are intentionally unchanged.

Validation

The new CI workflow runs flatpak-builder-lint for the manifest and AppStream file plus desktop-file-validate for the desktop entry.