Find missing tests in iti and iti-react

[molszanski]

Describe your changes

This PR introduces a suite of high-priority tests to enhance the robustness and reliability of both the iti and iti-react libraries. The new tests address critical production-ready scenarios, focusing on:

• Error Handling: Verifying proper detection and handling of circular dependencies and propagation of async factory errors in iti.
• Memory Leak Prevention: Ensuring correct cleanup of event listeners, subscriptions, and cached values upon disposal in iti, and proper component unmounting cleanup in iti-react.
• Concurrency Safety: Testing safe handling of simultaneous get(), upsert(), add(), dispose(), and getItemSet() operations, as well as race conditions in async factories within iti.
• React Integration: Validating that iti-react hooks prevent unnecessary re-renders, handle unmounting during async operations, and integrate correctly with disposers and multiple components.

These additions significantly improve coverage for scenarios vital for stable and performant applications.

Checklist before requesting a review

• I have performed a self-review of my code
• I did run tests on the whole monorepo

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