* Switch to the mise-bin package
mise-bin carries mise's own release artifacts from the Omarchy repo --
PGO+BOLT-optimized on x86_64, glibc-native on both arches -- instead of
Arch's mise, and tracks jdx/mise releases directly.
Existing installs need a migration because the two packages conflict, and
omarchy-pkg-add cannot make the swap: pacman answers its own conflict
question with No under --noconfirm and fails the transaction. --ask=4
answers that one question, so mise-bin replaces mise in a single
transaction -- which is also what keeps omarchy-zsh and omarchy-fish, both
of which depend on mise, satisfied through the swap by its provides.
* Guard the swap with a conditional instead of an early exit
Two-path control flow takes an if, per the style guide; the early exit only made the swap line unreachable from a distance.
