修复泥点悬浮窗与登录弹窗交互

桌面端泥点详情支持从按钮移动到浮层并取消点击保持
统一弹窗仅在完整遮罩指针序列后关闭
补充泥点悬浮与登录遮罩拖出回归测试
记录遮罩关闭交互约束

src/components/auth/PlatformAuthModalShell.test.tsx

@@ -30,7 +30,15 @@ test('renders auth modal shell with platform theme and auth card chrome', () =>
   expect(dialog.className).toContain('!max-w-md');
   expect(within(dialog).getByText('登录表单')).toBeTruthy();
 
-  fireEvent.click(dialog.parentElement as HTMLElement);
+  const backdrop = dialog.parentElement as HTMLElement;
+  fireEvent.pointerDown(within(dialog).getByText('登录表单'));
+  fireEvent.pointerUp(backdrop);
+  fireEvent.click(backdrop);
+  expect(onClose).not.toHaveBeenCalled();
+
+  fireEvent.pointerDown(backdrop);
+  fireEvent.pointerUp(backdrop);
+  fireEvent.click(backdrop);
   expect(onClose).toHaveBeenCalledTimes(1);
 });