Fix #5354: Replaced single-threaded scope with Actor

[manas-yu]

Explanation

Fix #5354
This PR addresses the issue where InMemoryBlockingCache was not guaranteed to process CRUD operations sequentially due to limitations in using a single-threaded dispatcher. The implementation has been updated to use an Actor, which ensures strict sequential processing of operations, thereby improving thread safety and atomicity.

• Replaced the single-threaded dispatcher-based coroutine scope with an Actor.
• Updated the internal state management logic to process CRUD operations exclusively within the Actor.
• Ensured all operations (create, read, update, delete) are processed in the correct order and no race conditions occur.

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