refactor: migrate Homebrew from RPM to Containerfile

[ahmedadan]

Summary

Migrates Homebrew from the ublue-brew RPM package to a pre-built tarball approach compatible with bootc's immutable
architecture, with runtime configuration moved to the common repo.

Changes

• Replaced ublue-brew RPM package with tarball-based installation:
  • Downloads pre-built tarball from ublue-os/packages releases to /usr/share/homebrew.tar.zst
  • Automatically fetches latest homebrew release
  • Verifies SHA256 checksum before inclusion in image
• brew-setup.service to extract tarball on first boot:
  • Extracts to /var/home/linuxbrew/.linuxbrew at runtime
  • Uses condition checks to run only once (/etc/.linuxbrew marker)
  • Sets proper ownership (UID 1000) after extraction
• Migrated Homebrew configuration to common repo:
  • Shell integration (bash, fish)
  • Systemd services and timers (brew-setup, brew-update, brew-upgrade)
  • Resource limits and tmpfiles.d configuration
• Removed ublue-brew package from ISO configurations
• Removed Brewfiles directory (moved to common repo)
• Removed just files (moved to common repo)
• Updated ISO configurations to disable brew services consistently

Dependencies

Requires projectbluefin/common#19 to be merged first.

[dosubot]

Related Documentation

2 document(s) may need updating based on files changed in this PR:

bluefin

• ISO Generation
• Update Process

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