debug iso: add menu command to relaunch tui

iso/overlay-debug/etc/profile.d/bee.sh

@@ -1,5 +1,14 @@
 export PATH="$PATH:/usr/local/bin"
 
+menu() {
+    if [ -x /usr/local/bin/bee-tui ]; then
+        /usr/local/bin/bee-tui "$@"
+    else
+        echo "bee-tui is not installed"
+        return 1
+    fi
+}
+
 # Auto-open TUI on local tty1 after boot.
 # Exiting TUI returns to this shell (console prompt).
 if [ -z "${BEE_TUI_AUTO_LAUNCHED:-}" ] \