DEV: Use `RenderGlimmer` for experimental user menu (#17597)

`RenderGlimmer` means we can now drop the classic-component wrapper. The old `didInsertElement` hook is reimplemented via the `did-insert` modifier.

app/assets/javascripts/discourse/app/components/user-menu-wrapper.js

@@ -1,12 +0,0 @@
-import Component from "@ember/component";
-import layout from "discourse/templates/components/user-menu-wrapper";
-
-export default Component.extend({
-  layout,
-  tagName: "",
-
-  didInsertElement() {
-    this._super(...arguments);
-    this.appEvents.trigger("user-menu:rendered");
-  },
-});

app/assets/javascripts/discourse/app/components/user-menu/menu.hbs

@@ -1,4 +1,4 @@
-<div class="user-menu revamped menu-panel drop-down" data-max-width="320">
+<div class="user-menu revamped menu-panel drop-down" data-max-width="320" {{did-insert this.triggerRenderedAppEvent}}>
   <div class="panel-body">
     <div class="panel-body-contents">
       <div

app/assets/javascripts/discourse/app/components/user-menu/menu.js

@@ -52,4 +52,9 @@ export default class UserMenu extends GlimmerComponent {
       this.currentPanelComponent = tab.panelComponent;
     }
   }
+
+  @action
+  triggerRenderedAppEvent() {
+    this.appEvents.trigger("user-menu:rendered");
+  }
 }

app/assets/javascripts/discourse/app/templates/components/user-menu-wrapper.hbs

@@ -1 +0,0 @@
-<UserMenu::Menu/>

app/assets/javascripts/discourse/app/widgets/header.js

@@ -11,7 +11,8 @@ import { schedule } from "@ember/runloop";
 import { scrollTop } from "discourse/mixins/scroll-top";
 import { wantsNewWindow } from "discourse/lib/intercept-click";
 import { logSearchLinkClick } from "discourse/lib/search";
-import ComponentConnector from "discourse/widgets/component-connector";
+import RenderGlimmer from "discourse/widgets/render-glimmer";
+import { hbs } from "ember-cli-htmlbars";
 
 const _extraHeaderIcons = [];
 
@@ -338,9 +339,11 @@ createWidget("revamped-user-menu-wrapper", {
 
   html() {
     return [
-      new ComponentConnector(this, "user-menu-wrapper", {}, [], {
-        applyStyle: false,
-      }),
+      new RenderGlimmer(
+        this,
+        "div.widget-component-connector",
+        hbs`<UserMenu::Menu />`
+      ),
     ];
   },