The previous check only matched "cdrom:" but Ubuntu 26 uses DEB822
format with "URIs: file:///cdrom". Now matches /cdrom broadly and
handles .sources files, .list files, and traditional sources.list.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
On minimal Ubuntu installs, the CD-ROM source persists in sources.list
and breaks apt-get update. Now detect and remove it before installing
git, and verify git is actually available after installation.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Split curl download from bash execution so network errors are caught
explicitly. Add post-install verification that brew is actually
available before reporting success.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>