Add dependencies for slash commands feature

Added @anthropic-ai/claude-agent-sdk, fuse.js, and gray-matter to support
   the slash commands implementation.

package.json

@@ -39,6 +39,7 @@
   "author": "Claude Code UI Contributors",
   "license": "MIT",
   "dependencies": {
+    "@anthropic-ai/claude-agent-sdk": "^0.1.29",
     "@codemirror/lang-css": "^6.3.1",
     "@codemirror/lang-html": "^6.4.9",
     "@codemirror/lang-javascript": "^6.2.4",
@@ -58,6 +59,8 @@
     "cors": "^2.8.5",
     "cross-spawn": "^7.0.3",
     "express": "^4.18.2",
+    "fuse.js": "^7.0.0",
+    "gray-matter": "^4.0.3",
     "jsonwebtoken": "^9.0.2",
     "lucide-react": "^0.515.0",
     "mime-types": "^3.0.1",