DataStructures.Lists. CircularBuffer is not thread safe.

DataStructures.Lists. CircularBuffer
Now
1,CircularBuffer.Add used by Producer threads
2,CircularBuffer.Add.Pop used by Consumer threads

Producer and Consumer is two different threads，when write the _count at the same time, the Count is not the desired value ！

The issue is in the CircularBuffer class in DataStructures/Lists. Examine the Add and Pop methods to see where _count is updated. Look for thread-safety mechanisms like locks or concurrent collections. Check if there are existing tests for CircularBuffer to understand expected behavior. The fix likely involves adding synchronization to ensure atomic updates to _count and other shared state.

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