Convert many examples to TypeScript (vercel#41825)

Strategized with @balazsorban44 to open one larger PR, with changes to individual examples as separate commits. 

For each example, I researched how multiple realworld codebases use the featured technology with TypeScript, to thoughtfully convert them by hand - nothing automated whatsoever.

## Documentation / Examples

- [X] Make sure the linting passes by running `pnpm lint`
- [X] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

Author: maxproske

examples/blog-with-comment/.prettierrc

@@ -1,13 +1,23 @@
 import { useAuth0 } from '@auth0/auth0-react'
 
-function CommentForm({ text, setText, onSubmit }) {
+type CommentFormProps = {
+  text: string
+  setText: Function
+  onSubmit: (e: React.FormEvent) => Promise<void>
+}
+
+export default function CommentForm({
+  text,
+  setText,
+  onSubmit,
+}: CommentFormProps) {
   const { isAuthenticated, logout, loginWithPopup } = useAuth0()
 
   return (
     <form onSubmit={onSubmit}>
       <textarea
         className="flex w-full max-h-40 p-3 rounded resize-y bg-gray-200 text-gray-900 placeholder-gray-500"
-        rows="2"
+        rows={2}
         placeholder={
           isAuthenticated
             ? `What are your thoughts?`
@@ -41,5 +51,3 @@ function CommentForm({ text, setText, onSubmit }) {
     </form>
   )
 }
-
-export default CommentForm