Improve examples

Only 3 examples are shown in the manual, so move the various cons adding
examples later since they are not helpful. As such, show an `interactive'
example, a Docstring result example and a square bracket args example.

Rename `example/add-cons' -> `example/interactive'.

dev/examples.el

@@ -1260,27 +1260,28 @@ new list."
     (funcall (-lambda (a (b c)) (+ a b c)) 1 (list 2 3)) => 6)
 
   (defexamples -defun
+    (progn (-defun example/interactive ((a . b))
+             "Add the `car' and `cdr' of INPUT0."
+             (interactive (list (cons 1 2)))
+             (+ a b))
+           (command-execute #'example/interactive)) => 3
+    (progn (-defun example/docstring-result ((&plist :x))
+             "Docstring and result.")
+           (example/docstring-result '(:x t))) => t
+    (progn (-defun example/square-args [&plist :x]
+             x)
+           (example/square-args '(:x t))) => t
+
     (progn (-defun example/cdr ((_ . tail)) tail)
            (example/cdr '(a . b))) => 'b
     (progn (-defun example/car ((cur)) cur)
            (example/car '(a . b))) => 'a
-    (progn (-defun example/add-cons ((a . b))
-             "Add the `car' and `cdr' of INPUT0."
-             (interactive (list (cons 1 2)))
-             (+ a b))
-           (command-execute #'example/add-cons)) => 3
     (progn (-defun example/add-conses-rec (&rest (cur . other))
              (if other
                  (+ (example/add-cons cur)
                     (apply #'example/add-conses-rec other))
                (example/add-cons cur)))
-           (example/add-conses-rec '(1 . 5) '(5 . 10))) => 21
-    (progn (-defun example/docstring-result ((&plist :x))
-             "Docstring and result.")
-           (example/docstring-result '(:x t))) => t
-    (progn (-defun example/square-args [&plist :x]
-             x)
-           (example/square-args '(:x t))) => t)
+           (example/add-conses-rec '(1 . 5) '(5 . 10))) => 21)
 
   (defexamples -defmacro
     (progn (-defmacro example/ht-query ((_query &as &plist :key) table)