Fix race condition in state.All() method (fixes #309)

[shanto12]

The state.All() method had a race condition where it unlocked the mutex inside the range loop over the map, leaving the map unprotected during iteration. This could trigger the race detector and cause concurrent map access issues.

This fix creates a copy of the map while holding the lock, then iterates over the copy without holding the lock. This ensures thread-safe iteration without blocking other operations for extended periods.

Fixes #309

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Summary of Changes

Hello @shanto12, I'm Gemini Code Assist[^1]! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves a critical race condition within the state.All() method, which previously exposed the underlying map to concurrent access issues during iteration. By adopting a copy-on-read approach, the change ensures that map iteration is performed on a consistent snapshot, thereby enhancing the stability and thread-safety of the system without introducing prolonged lock contention.

Highlights

• Race Condition Fix: Addressed a race condition in the state.All() method where the mutex was incorrectly unlocked during map iteration, potentially leading to concurrent map access issues.
• Thread-Safe Iteration: Implemented a thread-safe iteration strategy for the state.All() method by creating a copy of the map while holding a read lock, then iterating over this immutable copy without holding the lock, ensuring data consistency and preventing deadlocks.

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