chore: fix CI failures in Node.js 21+ and TypeScript type checking (#246)

* Initial plan

* Fix CI issues: navigator assignment and typecheck error

Co-authored-by: kentcdodds <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: kentcdodds <[email protected]>

Author: Copilot

src/__tests__/setup-tests.js

@@ -19,8 +19,12 @@ function copyProps(src, target) {
 // @ts-expect-error TS2322 🤷‍♂️
 global.window = window
 global.document = window.document
-// @ts-expect-error TS2740 🤷‍♂️
-global.navigator = {userAgent: 'node.js'}
+// Use Object.defineProperty to set navigator because in Node 21+ it's read-only
+Object.defineProperty(global, 'navigator', {
+  value: {userAgent: 'node.js'},
+  writable: true,
+  configurable: true,
+})
 global.requestAnimationFrame = callback => setTimeout(callback, 0)
 global.cancelAnimationFrame = id => clearTimeout(id)
 copyProps(window, global)

src/remark-mdx-images.d.ts

@@ -0,0 +1,6 @@
+// Type declaration override for remark-mdx-images to fix type compatibility issues
+declare module 'remark-mdx-images' {
+  import type {Plugin} from 'unified'
+  const remarkMdxImages: Plugin
+  export default remarkMdxImages
+}

tsconfig.json

@@ -8,6 +8,10 @@
     "checkJs": true,
     "lib": [
       "ES2021.String"
-    ]
-  }
+    ],
+    "skipLibCheck": true
+  },
+  "exclude": [
+    "node_modules"
+  ]
 }