v0.6.0: beautifului 整合 + 会话/工作区/队列/权限/命令/附件全链路

- beautifului.dev 组件直连：Sidebar Nav、Tool Chips、Approval Card（抽屉化）、Streaming/Thinking、Code Block、Selection Actions、Prompt Bar、Search

apps/desktop/preview/index.html

@@ -0,0 +1,12 @@
+<!doctype html>
+<html lang="zh-CN">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>beautifului primitives preview</title>
+  </head>
+  <body class="bg-zinc-50 text-zinc-900">
+    <div id="root"></div>
+    <script type="module" src="./main.tsx"></script>
+  </body>
+</html>