[feat] add DeepSeek Harness sidebar support and setup guides

apps/mcp/package.json

@@ -18,7 +18,7 @@
     "crossdesk-mcp": "dist/main.js"
   },
   "scripts": {
-    "build": "tsc && tsc -p tsconfig.ui.json && node scripts/build-ui.mjs",
+    "build": "tsc && tsc -p tsconfig.ui.json && node scripts/build-ui.mjs && node scripts/build-harness.mjs",
     "check": "tsc --noEmit && tsc -p tsconfig.ui.json",
     "pack:npm": "node scripts/pack.mjs"
   },