build(mcp): add MCP SDK, zod and tsx for the agent tool layer

zod was previously only a transitive dependency; declared explicitly so
it cannot vanish under a dependency bump. tsx rather than Node's native
type stripping because the metrics modules import via the @/* alias,
which Node does not resolve.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

package.json

@@ -11,10 +11,12 @@
     "typecheck": "tsc --noEmit",
     "test": "vitest",
     "test:run": "vitest run",
+    "mcp": "tsx --env-file=.env.local src/mcp/server.ts",
     "postinstall": "node scripts/patch-next-dev-blocker.cjs"
   },
   "dependencies": {
     "@ducanh2912/next-pwa": "^10.2.9",
+    "@modelcontextprotocol/sdk": "^1.30.0",
     "@n8n/workflow-sdk": "^0.29.3",
     "@radix-ui/react-dialog": "^1.1.4",
     "@radix-ui/react-dropdown-menu": "^2.1.4",
@@ -35,7 +37,8 @@
     "react-dom": "^19.0.0",
     "recharts": "^2.15.0",
     "tailwind-merge": "^2.6.0",
-    "xlsx": "^0.18.5"
+    "xlsx": "^0.18.5",
+    "zod": "^3.25.76"
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4.0.0",
@@ -47,6 +50,7 @@
     "eslint-config-next": "^16",
     "postcss": "^8.4.49",
     "tailwindcss": "^4.0.0",
+    "tsx": "^4.23.12",
     "typescript": "^5.7.2",
     "vitest": "^2.1.9"
   }