style(config): Reformat Emacs Lisp code for consistency

Standardize formatting across multiple init files: expand
single-line use-package keywords onto separate lines, fix
indentation, remove outdated comments, and clean up whitespace. Also
adds mc/keymap <return> binding and improves fcitx5 startup logic in
EXWM.

lisp/init-kbd.el

@@ -177,6 +177,10 @@
 (general-def calendar-mode-map
   "RET" 'denote-journal-calendar-find-file)
 
+;; multiple-cursor
+(general-def mc/keymap
+  "<return>" 'newline)
+
 ;; emms
 (general-def emms-playlist-mode-map
   "<prior>" 'emms-previous
@@ -272,7 +276,7 @@
                    (lambda (buffer) (diff-buffer-with-file (buffer-file-name buffer)))
                    "show diff between the buffer and its file"))
 
-;; multiple-cursors
+;; multiple-cursors hydra
 (defhydra hydra-multiple-cursors ()
   "
      ^Mark^                    ^Unmark^              ^Other^