Bug: Suspense component missing fallback prop in hooks.md

Description

In pages/hooks.md, the <Suspense> component is used without the required fallback prop.

Location

File: pages/hooks.md
Line: 602

Current Code

return (
  <Suspense>
    <ul>
      {users.map((user) => (
        <div key={user.id}>
          ...
        </div>
      ))}
    </ul>
  </Suspense>
)

Expected Code

return (
  <Suspense fallback={<div>Loading...</div>}>
    <ul>
      {users.map((user) => (
        <div key={user.id}>
          ...
        </div>
      ))}
    </ul>
  </Suspense>
)

Why This Matters

• The fallback prop is required for Suspense to display a loading state while async content resolves
• Without it, users see nothing while data is loading, resulting in poor UX
• This is a teaching material, so it should demonstrate correct usage

References

• React Suspense Docs

Open pages/hooks.md around line 602 and compare the Suspense example with the linked React Suspense documentation. Update the teaching example to demonstrate the required fallback behavior, then re-read the example to confirm the loading-state usage is clear and complete.