[mcp] Add inspect script (facebook#32928)

Uses https://github.com/modelcontextprotocol/inspector to inspect and
debug the mcp server.

`yarn workspace react-mcp-server dev` will build the server in watch
mode and launch the inspector. Default address is http://127.0.0.1:6274.
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[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/32928).
* facebook#32932
* facebook#32931
* facebook#32930
* facebook#32929
* __->__ facebook#32928

Author: poteto

compiler/packages/react-mcp-server/package.json

@@ -8,6 +8,8 @@
   "scripts": {
     "build": "rimraf dist && tsup",
     "test": "echo 'no tests'",
+    "dev": "concurrently --kill-others -n build,inspect \"yarn run watch\" \"wait-on dist/index.js && yarn run inspect\"",
+    "inspect": "npx @modelcontextprotocol/inspector node dist/index.js",
     "watch": "yarn build --watch"
   },
   "dependencies": {