DEV: Cleanup ace-editor event listeners (#27844)

- set in constructor so they're guaranteed to be present, even if async-import hasn't finished yet
- ensure they're all cleaned up properly
- combine two cleanup methods into one

app/assets/javascripts/admin/addon/components/ace-editor.js

@@ -2,7 +2,7 @@ import Component from "@ember/component";
 import { action } from "@ember/object";
 import { next } from "@ember/runloop";
 import { classNames } from "@ember-decorators/component";
-import { observes, on } from "@ember-decorators/object";
+import { observes } from "@ember-decorators/object";
 import loadAce from "discourse/lib/load-ace-editor";
 import { bind } from "discourse-common/utils/decorators";
 import I18n from "discourse-i18n";
@@ -19,6 +19,14 @@ export default class AceEditor extends Component {
   _editor = null;
   _skipContentChangeEvent = null;
 
+  constructor() {
+    super(...arguments);
+    this.appEvents.on("ace:resize", this.resize);
+    window.addEventListener("resize", this.resize);
+    this._darkModeListener = window.matchMedia("(prefers-color-scheme: dark)");
+    this._darkModeListener.addListener(this.setAceTheme);
+  }
+
   @observes("editorId")
   editorIdChanged() {
     if (this.autofocus) {
@@ -73,17 +81,6 @@ export default class AceEditor extends Component {
     }
   }
 
-  @on("willDestroyElement")
-  _destroyEditor() {
-    if (this._editor) {
-      this._editor.destroy();
-      this._editor = null;
-    }
-
-    this.appEvents.off("ace:resize", this.resize);
-    window.removeEventListener("resize", this.resize);
-  }
-
   @action
   resize() {
     if (this._editor) {
@@ -145,29 +142,25 @@ export default class AceEditor extends Component {
       this.changeDisabledState();
       this.warnSCSSDeprecations();
 
-      window.addEventListener("resize", this.resize);
-
-      this.appEvents.on("ace:resize", this.resize);
-
       if (this.autofocus) {
         this.send("focus");
       }
 
       this.setAceTheme();
-
-      this._darkModeListener = window.matchMedia(
-        "(prefers-color-scheme: dark)"
-      );
-      this._darkModeListener.addListener(this.setAceTheme);
     });
   }
 
   willDestroyElement() {
+    if (this._editor) {
+      this._editor.destroy();
+      this._editor = null;
+    }
+
     super.willDestroyElement(...arguments);
+
     this._darkModeListener?.removeListener(this.setAceTheme);
-    window.addEventListener("resize", () => {
+    window.removeEventListener("resize", this.resize);
-      this.appEvents.trigger("ace:resize");
+    this.appEvents.off("ace:resize", this.resize);
-    });
   }
 
   get aceTheme() {