💥 Remove :feature category

:feature was a "catch-all" category. Many of its modules fit better in
other categories, so they've been moved:

- feature/debugger -> tools/debugger
- feature/evil -> editor/evil
- feature/eval -> tools/eval
- feature/lookup -> tools/lookup
- feature/snippets -> editor/snippets
- feature/file-templates -> editor/file-templates
- feature/workspaces -> ui/workspaces

More potential changes in the future:

- A new :term category for terminal emulation modules (eshell, term and
  vterm).
- A new :os category for modules dedicated to os-specific functionality.
  The :tools macos module would fit here, but so would modules for nixos
  and arch.
- A new :services category for web-service integration, like wakatime,
  twitter, elfeed, gist and pastebin services.

modules/tools/debugger/autoload/debug.el

@@ -0,0 +1,11 @@
+;;; tools/debugger/autoload/debug.el -*- lexical-binding: t; -*-
+
+;;;###autoload
+(defun +debugger/quit ()
+  "Quit the active debugger, if any."
+  (interactive)
+  (ignore-errors (call-interactively #'realgud:cmd-quit))
+  (doom/popup-close)
+  (when (featurep 'evil)
+    (evil-normal-state)))
+