fix: move stty size to first priority in backend-size

stty size via subprocess is the most reliable method — it
returns the correct 59x83 from the user's terminal. Move it
before ioctl to ensure it's tried first.

src/backend/simple.lisp

@@ -22,7 +22,19 @@
   (values))
 
 (defmethod backend-size ((b simple-backend))
-  (or (ignore-errors
+  (or ;; stty size via subprocess — most reliable across all systems.
+      (ignore-errors
+        (let* ((out (uiop:run-program '("sh" "-c" "stty size < /dev/tty")
+                                      :output :string
+                                      :ignore-error-status t))
+               (parts (and out (uiop:split-string
+                                 (string-trim '(#\newline #\space) out)))))
+          (when (and parts (= (length parts) 2))
+            (let ((rows (parse-integer (first parts) :junk-allowed t))
+                  (cols (parse-integer (second parts) :junk-allowed t)))
+              (when (and rows cols (> rows 0) (> cols 0))
+                (values cols rows))))))
+      (ignore-errors
         (let* ((+tiocgwinsz+ 21523)
                (winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))
           (unwind-protect