fix(desktop): bump asset cache-bust (css v21/js v29) so chip styles load; make chip bg more visible

frontends/desktop/static/index.html

@@ -3,7 +3,7 @@
 <head>
 <meta charset="UTF-8">
 <title>GenericAgent</title>
-<link rel="stylesheet" href="styles.css?v=20">
+<link rel="stylesheet" href="styles.css?v=21">
 <!-- KaTeX: LaTeX 公式渲染 -->
 <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.16.11/dist/katex.min.css" crossorigin="anonymous">
 <!-- highlight.js: 代码高亮 -->
@@ -451,7 +451,7 @@
 <script src="https://cdn.jsdelivr.net/npm/katex@0.16.11/dist/katex.min.js" crossorigin="anonymous"></script>
 <!-- highlight.js -->
 <script src="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.9.0/build/highlight.min.js" crossorigin="anonymous"></script>
-<script src="app.js?v=28"></script>
+<script src="app.js?v=29"></script>
 <script src="annot.js"></script><!-- DEV 脚手架，可删 -->
 </body>
 </html>

frontends/desktop/static/styles.css

@@ -801,7 +801,7 @@ html[data-boot-has-sessions] .chat-start{ display:none !important; }
 .ph-chip{
   display:inline-flex; align-items:center; vertical-align:baseline;
   margin:0 2px; padding:1px 8px; border-radius:6px;
-  background:color-mix(in srgb, var(--blue) 16%, transparent); color:var(--blue);
+  background:color-mix(in srgb, var(--blue) 22%, transparent); color:var(--blue);
   font-size:.9em; white-space:nowrap; user-select:none; cursor:default;
 }
 .composer-bot{ display:flex; align-items:center; justify-content:space-between; margin-top:8px; }