✨ Quality: Improve robustness and documentation of AsyncBlock

[galiprandi]

💡 What: The quality improvement added

Implemented several enhancements to the AsyncBlock component:

• Race Condition Fix: Updated the .catch block logic to use signal.reason to distinguish between manual aborts (from dependency changes/unmounts) and timeout aborts. This prevents the component from incorrectly showing an error state when it's just being re-triggered or unmounted.
• API Flexibility: Made the error prop optional in AsyncBlockProps, allowing consumers to omit it if they don't need a specific error UI.
• Documentation: Added detailed JSDoc for the component and all its props, including a template parameter and usage examples.
• Test Coverage: Added new tests to verify the race condition fix and the optional error prop behavior. Improved existing tests with proper mock cleanup.

🎯 Why: The quality gap it addresses

The previous implementation had a potential race condition where aborted promises could overwrite the state of a new request. Additionally, the component was lackings sufficient documentation and had a strictly required error prop that wasn't always necessary.

📊 Impact: How it improves the codebase

• Increased Robustness: Fewer UI glitches during rapid dependency changes.
• Better Developer Experience: Clearer documentation and examples make the component easier to adopt.
• Higher Maintainability: The test suite is more robust and isolated.

✅ Verification: How to verify it works

Run pnpm test lib/components/AsyncBlock/index.test.tsx to verify the new and existing tests pass.
Run pnpm lint to ensure the changes follow the project's coding standards.

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PR created automatically by Jules for task 14959684732361421922 started by @galiprandi

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