fix(test-server): make msw a production dependency (#9999)

## Background

We introduced a new package for the test server in #8588. The test
server always depended on `msw`, but we didn't add it as production
dependency because before we created a dedicated package for it, it was
part of provider-utils. Making `msw` a production dependency would have
meant that installing `ai` would install `msw` without ever needing it.

## Summary

`msw` will now automatically installed when installing
`@ai-sdk/test-server`. It's already fixed it in the `main` branch via
#9988

## Manual Verification

I'll try after the release but I'm sure enough this works as designed.

## Related Issues

#8588, #9988

Author: gr2m

packages/test-server/package.json

@@ -37,11 +37,13 @@
       "require": "./dist/with-vitest.js"
     }
   },
+  "dependencies": {
+    "msw": "^2.7.0"
+  },
   "devDependencies": {
     "@types/node": "20.17.24",
     "@vercel/ai-tsconfig": "workspace:*",
     "tsup": "^8",
-    "msw": "^2.7.0",
     "typescript": "5.8.3"
   },
   "engines": {

packages/test-server/tsconfig.json

@@ -13,11 +13,6 @@
       "build",
       "node_modules",
       "tsup.config.ts"
-    ],
-    "references": [
-        {
-        "path": "../provider"
-        }
     ]
   }