feat: RAG, memory, plugins, lessons, file editor, split panes, Markdown rendering, PWA + UI overhaul

Major additions:
- RAG pipeline (indexing, chunking, search) with sidebar upload button
- Memory system with CRUD API
- Plugins and lessons modules
- MCP discovery and MCP server
- Advanced skills (auto-create, conditional, improver)
- Agent browser/image support, delegate, sessions
- File editor with CodeMirror in split panes
- Markdown rendering via react-markdown + KaTeX + highlight.js
- Raw markdown toggle
- PWA manifest + service worker
- Extension UI redesign with new design tokens and studio-style chat
- Pipeline API for chat streaming
- Mobile responsive layout

💘 Generated with Crush

Assisted-by: GLM-5.1 via Crush <crush@charm.land>

web/public/manifest.json

@@ -0,0 +1,28 @@
+{
+  "name": "Muyue",
+  "short_name": "Muyue",
+  "description": "AI-powered development environment",
+  "start_url": "/",
+  "display": "standalone",
+  "background_color": "#0A0A0C",
+  "theme_color": "#FF0033",
+  "orientation": "any",
+  "icons": [
+    {
+      "src": "/muyue-64.png",
+      "sizes": "64x64",
+      "type": "image/png"
+    },
+    {
+      "src": "/muyue.png",
+      "sizes": "128x128",
+      "type": "image/png"
+    },
+    {
+      "src": "/favicon-32.png",
+      "sizes": "32x32",
+      "type": "image/png"
+    }
+  ],
+  "categories": ["developer tools", "productivity"]
+}