feat(keybindings): add cmd+shift+p and cmd+/ keybindings from VSCode

Makes cmd+shift+p open the command palette and cmd+/ toggle comments, as
they do in VSCode.

This should ease my recent usage of Cursor/VSCode alongside Emacs, as
certain keybindings I have in Emacs cannot be setup in VSCode to work in
all contexts. Hence I've had to get used to cmd+shift+p instead of C-x
C-m, as the later does not want to play ball when a terminal is active
in VSCode.

modules/text-editing/siren-toggle-comments.el

@@ -10,6 +10,7 @@
   :straight (:type built-in)
 
   :general
+  ("s-/" 'comment-or-uncomment-region-or-line)
   ("C-c /" 'comment-or-uncomment-region-or-line)
   ("C-c C-/" 'comment-or-uncomment-region-or-line)
   ("C-c C-_" 'comment-or-uncomment-region-or-line)