Adds an "Enable AUR" entry to the global menu allowing the user to
choose between paru and yay. The selected helper is built from source
inside the chroot, running as the first sudo user under a temporary
NOPASSWD-pacman sudoers entry that is removed in a finally block.
Source builds avoid the libalpm soname mismatch that can occur with
prebuilt -bin packages.
The feature gracefully no-ops when no AUR helper is configured. The
menu item is gated behind the presence of a regular user account;
attempting --silent installs without one raises RequirementError.
Signed-off-by: pentago <876756+pentago@users.noreply.github.com>
817a1adef3