Bump @modelcontextprotocol/sdk in /samples/Whiteboard/MCPServer (#331)

Bumps [@modelcontextprotocol/sdk](https://github.com/modelcontextprotocol/typescript-sdk) from 1.24.0 to 1.25.2.
- [Release notes](https://github.com/modelcontextprotocol/typescript-sdk/releases)
- [Commits](modelcontextprotocol/typescript-sdk@1.24.0...v1.25.2)

---
updated-dependencies:
- dependency-name: "@modelcontextprotocol/sdk"
  dependency-version: 1.25.2
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

samples/Whiteboard/MCPServer/package-lock.json

@@ -12,7 +12,7 @@
   "type": "module",
   "dependencies": {
     "@microsoft/signalr": "^8.0.7",
-    "@modelcontextprotocol/sdk": "^1.24.0",
+    "@modelcontextprotocol/sdk": "^1.25.2",
     "dotenv": "^16.4.7"
   }
 }