Expand multiple build capabilities

usr-common/share/ublue-os/firstboot/launcher/autostart.desktop

@@ -0,0 +1,9 @@
+[Desktop Entry]
+Name=uBlue First Boot Setup
+Comment=Sets up the uBlue desktop on first boot.
+GenericName=Launcher
+Categories=Utility;System;
+Exec=/usr/share/ublue-os/firstboot/launcher/autostart.sh
+Icon=application-x-executable
+Terminal=false
+Type=Application

usr-common/share/ublue-os/firstboot/launcher/autostart.sh

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+#!/usr/bin/env bash
+
+# Simply launches the "yafti" GUI with the uBlue image's configuration.
+/usr/bin/yafti /usr/share/ublue-os/firstboot/yafti.yml

usr-common/share/ublue-os/firstboot/launcher/login-profile.sh

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+# Only process users with home directories, but skip the "root" user.
+if [ "$(id -u)" != "0" ] && [ ! -z "$HOME" ] && [ -d "$HOME" ]; then
+    # Ensure target file exists and is a symlink (not a regular file or dir).
+    if [ ! -L "$HOME"/.config/autostart/ublue-firstboot.desktop ]; then
+        # Remove any leftovers or incorrect (non-link) files with the same name.
+        rm -rf "$HOME"/.config/autostart/ublue-firstboot.desktop
+
+        # Create symlink to uBlue's autostart runner.
+        # Note that "broken autostart symlinks" are harmless if they remain
+        # after distro switching, and just cause a minor syslog warning. The
+        # user can manually delete this file if they migrate away from uBlue.
+        mkdir -p "$HOME"/.config/autostart
+        ln -s "/usr/share/ublue-os/firstboot/launcher/autostart.desktop" "$HOME"/.config/autostart/ublue-firstboot.desktop
+    fi
+fi