✨ Quality: documentation and test coverage - AsyncBlock

[galiprandi]

I have implemented several micro-quality improvements for the AsyncBlock component:

1. Documentation Enhancement: Updated the JSDoc for the AsyncBlock component and its props to be more descriptive. Added a comprehensive @example that demonstrates advanced usage, including the reload function in pending, success, and error states, as well as the onSuccess and onError callbacks.
2. Test Coverage Improvement: Added new test cases to lib/components/AsyncBlock/index.test.tsx to cover previously untested branches and edge cases:
   • Verified that timeouts are correctly cleared when a promise resolves or rejects.
   • Ensured that callbacks (onSuccess, onError) are not called if the component is unmounted or the operation is aborted due to dependency changes.
   • Exercised the pending state when provided as a function.
3. Test Robustness: Centralized the reset of fake timers in an afterEach block to prevent potential test flakiness and ensure a clean environment for subsequent tests.
4. Maintainability: Preserved explicit state guards in the component to ensure runtime safety, even when they appear logically exhaustive in the current implementation.

These changes make the AsyncBlock component easier to use through better documentation and more reliable through increased test verification.

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PR created automatically by Jules for task 4211219009960061019 started by @galiprandi

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