style(frontend): 接入 stash-ui 设计系统

- 依赖 @stash/ui（file:../../stash-ui），统一引入 style.css 与 Toaster
- 任务面板、表单、弹窗、日志、状态标签全部迁到组件库，App.css 只保留页面布局
- 移除自写 useFocusTrap，改用基于原生 dialog 的 Modal
- 修复 LogViewer 流式追加时误判离开底部、导致不再自动跟随的问题
- 发布脚本检查 stash-ui 产物；README 补充组件库构建与 file: 依赖刷新说明

frontend/pnpm-lock.yaml

@@ -11,6 +11,9 @@ importers:
       '@hookform/resolvers':
         specifier: ^5.9.2
         version: 5.9.2([email protected](@types/[email protected])([email protected]))([email protected])
+      '@stash/ui':
+        specifier: file:../../stash-ui
+        version: file:../../stash-ui([email protected]([email protected]))([email protected])
       '@tanstack/react-query':
         specifier: ^5.104.3
         version: 5.104.3([email protected])
@@ -477,6 +480,12 @@ packages:
   '@standard-schema/[email protected]':
     resolution: {integrity: sha512-e7Mew686owMaPJVNNLs55PUvgz371nKgwsc4vxE49zsODpJEnxgxRo2y/OKrqueavXgZNMDVj3DdHFlaSAeU8g==}
 
+  '@stash/ui@file:../../stash-ui':
+    resolution: {directory: ../../stash-ui, type: directory}
+    peerDependencies:
+      react: '>=19'
+      react-dom: '>=19'
+
   '@tanstack/[email protected]':
     resolution: {integrity: sha512-DZY9TuJAOgU3UyHUhXb4CcTYEHNZszlwkPg4VViIwTxOKzLprPUU+rbaPZQd3srqkGOtpaDdKpW972UV/LKlcg==}
 
@@ -1361,6 +1370,11 @@ snapshots:
 
   '@standard-schema/[email protected]': {}
 
+  '@stash/ui@file:../../stash-ui([email protected]([email protected]))([email protected])':
+    dependencies:
+      react: 19.3.1
+      react-dom: 19.3.1([email protected])
+
   '@tanstack/[email protected]': {}
 
   '@tanstack/[email protected]([email protected])':