completion/selectrum -> completion/vertico, part 2

- Rename module from `:completion selectrum` to `:completion vertico`
- Rename all files involved
- Do *not* yet rename all the functions, as that messes up git's rename
  detection.

modules/app/irc/autoload/vertico.el

@@ -0,0 +1,23 @@
+;;; app/irc/autoload/vertico.el -*- lexical-binding: t; -*-
+;;;###if (featurep! :completion vertico)
+
+;;;###autoload
+(defun +irc/selectrum-jump-to-channel ()
+  "Jump to an open channel or server buffer with vertico."
+  (interactive)
+  (require 'consult)
+  (consult--multi (list (plist-put (copy-sequence +irc--consult-circe-source)
+                                   :hidden nil))
+                  :narrow nil
+                  :require-match t
+                  :prompt "Jump to:"
+                  :sort nil))
+
+;;;###autoload
+(defvar +irc--consult-circe-source
+        `(:name     "circe"
+          :hidden   t
+          :narrow   ?c
+          :category buffer
+          :state    ,#'consult--buffer-state
+          :items    ,(lambda () (mapcar #'buffer-name (+irc--circe-all-buffers)))))