refactor: introduce doom-module-context

Where f9201eb introduced a general context system, this one introduces
one for modules, to simplify our let-bind game when interacting with
modules, and to more efficiently expose module state to modulep! (which
gets called at runtime a great deal, so its performance is important).

* lisp/doom-lib.el (doom-log): simplify macro and introduce
  doom-inhibit-log variable.
* lisp/doom-modules.el (modulep!): fix reported file path if modulep!
  fails to find the local module.
* lisp/lib/debug.el (doom-debug-variables): disable doom-inhibit-log
  when debug mode is on.

Ref: f9201eb218

modules/lang/org/config.el

@@ -1351,7 +1351,7 @@ between the two."
       ))
 
   ;;; Custom org modules
-  (dolist (flag doom--current-flags)
+  (dolist (flag (doom-module-context-get 'flags))
     (load! (concat "contrib/" (substring (symbol-name flag) 1)) nil t))
 
   ;; Add our general hooks after the submodules, so that any hooks the