emacs: Add and enable combobulate package

..by Mickey Patterson, of Mastering Emacs fame.

The package is supposed to provide finer and nicer structural editing
experience, aided by new treesit(*-ts)-modes, but currently, I use none.

The only tree-sitter mode I currently use extensively is nix-mode, and
it integrates using external tree-sitter module, so as of this commit,
combobulate is fairly useless for me.

Now, doom's development has slowed down significantly, and I foresee
problems on the horizon with these new hodgpodge of tree-sitter modules,
so we'll see.

hosts/hermes/doom/config.org

@@ -171,6 +171,9 @@ Tangle ~packages.el~ from within org-mode.
   :recipe (:type git :host github :repo "lazzalazza/org-footnote-assistant"))
 
 (package! exercism)
+
+(package! combobulate
+  :recipe (:type git :host github :repo "mickeynp/combobulate"))
 #+end_src
 * Modus-themes
 Customize Modus-themes a little to make it more peppy and vibrant.
@@ -1122,3 +1125,18 @@ When Emacs is opened in Windows Subsystem for Linux, open web links in Firefox o
 (use-package! exercism
   :commands (exercism))
 #+end_src
+
+** Combobulate
+#+begin_src emacs-lisp :lexical t
+(use-package combobulate
+  :preface
+  (setq combobulate-key-prefix "C-c o")
+  ;; You can manually enable Combobulate with `M-x
+  ;; combobulate-mode'.
+  :after (treesit)
+  :hook ((nix-mode . combobulate-mode)
+         (python-ts-mode . combobulate-mode)
+         (js-ts-mode . combobulate-mode)
+         (css-ts-mode . combobulate-mode)
+         (yaml-ts-mode . combobulate-mode)))
+#+end_src