iter(g27): 抽出弹层 Esc 栈，多弹层只关最上层

packages/skin/ui/src/drawer.ts

@@ -1,5 +1,6 @@
 import { effect, h } from '@ui-arch/frame';
 import type { DrawerProps } from './types.js';
+import { pushOverlay } from './overlay.js';
 
 /*** 抽屉：open 信号驱动侧滑面板，点遮罩 / × / Esc 关闭；Tab 焦点陷阱 + 关闭归还焦点，与 modal 的分工是不打断主视图、可从侧边保留上下文 ***/
 export function drawer(props: DrawerProps, ...children: unknown[]): HTMLElement {
@@ -29,15 +30,19 @@ export function drawer(props: DrawerProps, ...children: unknown[]): HTMLElement
   overlay.append(panel);
 
   let lastFocus: HTMLElement | null = null; // 打开前焦点宿主，关闭时归还
+  let release: (() => void) | null = null; // Esc 栈注销函数，关闭时释放
   const focusables = (): HTMLElement[] =>
     Array.from(panel.querySelectorAll<HTMLElement>('button, [href], input, select, textarea, [tabindex]:not([tabindex="-1"])'))
       .filter((el) => !el.hasAttribute('disabled')); // 面板内可聚焦元素（排除禁用）
   effect(() => {
     if (props.open()) {
       lastFocus = document.activeElement as HTMLElement | null; // 记录打开前焦点
+      release ??= pushOverlay(close); // 入 Esc 栈：多弹层时只关最上层
       (panel.querySelector('button, input, textarea') as HTMLElement | null)?.focus(); // 打开时聚焦首个可交互元素
-    } else if (lastFocus) {
-      lastFocus.focus(); // 关闭时归还焦点
+    } else {
+      release?.(); // 出 Esc 栈
+      release = null;
+      lastFocus?.focus(); // 关闭时归还焦点
       lastFocus = null;
     }
   });
@@ -53,8 +58,5 @@ export function drawer(props: DrawerProps, ...children: unknown[]): HTMLElement
       e.preventDefault(); first.focus(); // Tab 到末位时回绕到开头
     }
   });
-  document.addEventListener('keydown', (e: KeyboardEvent) => {
-    if (e.key === 'Escape' && props.open()) close();
-  });
   return overlay;
 }