cfg/os-release was not being copied, causing NAME to remain 'Arch Linux'
instead of 'aios'.
Added os-release copy to both:
- build.zsh
- .github/workflows/release.yml
archiso now creates bootstrap with systemd-nspawn standard structure:
root.x86_64/var/lib/machines/arch/ instead of root.x86_64/
Changes:
- build.zsh: Updated all arch-chroot paths to root.x86_64/var/lib/machines/arch
- build.zsh: Updated file copy paths for .zshrc, mcp.json, config.toml
- .github/workflows/release.yml: Same path updates
- Added aigpt + Claude Code installation steps to GitHub Actions
This aligns with systemd-nspawn's standard container directory structure
(/var/lib/machines/).
