Add terminal and addon refs to all windows

demo/components/window/baseWindow.ts

@@ -0,0 +1,29 @@
+/**
+ * Copyright (c) 2025 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+/// <reference path="../../../typings/xterm.d.ts"/>
+
+import type { AddonCollection } from '../../types';
+import type { IControlWindow } from '../controlBar';
+import type { Terminal } from '@xterm/xterm';
+
+export abstract class BaseWindow implements IControlWindow {
+    protected get _terminal(): Terminal { return this.__terminal; }
+
+    constructor(
+        private __terminal: Terminal,
+        protected readonly _addons: AddonCollection,
+    ) {
+
+    }
+
+    setTerminal(terminal: Terminal): void {
+        this.__terminal = terminal;
+    }
+
+    abstract id: string;
+    abstract label: string;
+    abstract build(container: HTMLElement): void;
+}