Bail out of the mise stub if the install fails

Saves a second, murkier error from the exec that would follow.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

bin/omarchy-mise-install

@@ -16,8 +16,8 @@ mkdir -p "$HOME/.local/bin"
 
 cat >"$HOME/.local/bin/$command" <<EOF
 #!/bin/bash
-mise use -g "$package"
-exec mise exec "$package" -- "$bin" "\$@"
+mise use -g "$package" || exit 1
+exec mise x "$package" -- "$bin" "\$@"
 EOF
 
 chmod +x "$HOME/.local/bin/$command"