chore: add Linux release installer workflow

[AhmedAredah]

Summary

• Add a tag/manual Release workflow that builds a Linux Qt Installer Framework .run installer.
• Fetch Container from the private v0.2.0 release tag with CONTAINER_REPO_TOKEN and KDReports from kdreports-2.3.0.
• Upload the installer and SHA256SUMS as workflow artifacts, and attach them to v* GitHub Releases.
• Defer Windows and macOS installers to a follow-up.

Notes

• The release workflow requires the existing CONTAINER_REPO_TOKEN secret.
• The workflow is tag/manual-triggered, so it should be validated with workflow_dispatch or a v* tag after merge.

Test plan

• git diff --check
• Parsed .github/workflows/release.yml with Ruby YAML locally
• After merge, run workflow_dispatch or push a v* tag and confirm the Linux installer artifact and release assets are produced