fix: setup wizard non-interactive safe, TUI script daemon detection + timing

lisp/system-config.lisp

@@ -53,10 +53,11 @@
       (config-write config))))
 
 (defun prompt (prompt-text)
-  "Simple prompt that returns user input as a string."
+  "Simple prompt that returns user input as a string.
+Returns nil if stdin is non-interactive."
   (format t "~a" prompt-text)
   (finish-output)
-  (read-line))
+  (ignore-errors (read-line)))
 
 (defun prompt-yes-no (prompt-text)
   "Prompts yes/no question. Returns T for yes, nil for no."