WebUI: Fix memory leak

See #22734, there is a memory leak in the MooTools .destroy(), this replaces all uses of that with the browser native .remove().

This also overrides the MooTools Document.id function, which is used by $(id). The original function always allocates an ID to elements it selects, the override doesn't, and is also a little more efficient.

Closes #22734.
PR  #22754.

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Co-authored-by: Chocobo1 <Chocobo1@users.noreply.github.com>

src/webui/www/private/scripts/contextmenu.js

@@ -478,7 +478,7 @@ window.qBittorrent.ContextMenu ??= (() => {
 
         updateCategoriesSubMenu(categories) {
             const contextCategoryList = document.getElementById("contextCategoryList");
-            [...contextCategoryList.children].forEach((el) => { el.destroy(); });
+            [...contextCategoryList.children].forEach((el) => { el.remove(); });
 
             const createMenuItem = (text, imgURL, clickFn) => {
                 const anchor = document.createElement("a");