Add defgroup vterm-mgt for vterm-mgt

In the past I used `defconst` in many of my Elisp libraries where I should've
used something like:

```elisp
;; some/path/to/some-lib.el

(defgroup some-lib nil)

(defcustom some-lib-setting nil
  :group 'some-lib)
```

When I encounter code that I should've structured this way, I'm cleaning it up
to prefer this more idiomatic pattern.

1 files changed, 9 insertions, 4 deletions

diff --git a/emacs/.emacs.d/wpc/vterm-mgt.el b/emacs/.emacs.d/wpc/vterm-mgt.el
index e33a134295..ce60bab149 100644
--- a/emacs/.emacs.d/wpc/vterm-mgt.el
+++ b/emacs/.emacs.d/wpc/vterm-mgt.el
@@ -31,11 +31,16 @@
 ;; Configuration
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(defconst vterm-mgt--instances (cycle-new)
-  "A cycle tracking all of my vterm instances.")
+(defgroup vterm-mgt nil
+  "Customization options for `vterm-mgt'.")
 
 (defcustom vterm-mgt-scroll-on-focus nil
-  "When t, call `end-of-buffer' after focusing a vterm instance.")
+  "When t, call `end-of-buffer' after focusing a vterm instance."
+  :type '(boolean)
+  :group 'vterm-mgt)
+
+(defconst vterm-mgt--instances (cycle-new)
+  "A cycle tracking all of my vterm instances.")
 
 (defun vterm-mgt--instance? (b)
   "Return t if the buffer B is a vterm instance."
@@ -113,7 +118,7 @@ This function should be called from a buffer running vterm."
 
 If for whatever reason, the state of `vterm-mgt--instances' is corrupted and
   misaligns with the state of vterm buffers in Emacs, use this function to
-  attempt to restore the state."
+  restore the state."
   (interactive)
   (setq vterm-mgt--instances
         (->> (buffer-list)