bugfix: fix potential thread-safety issue in BacktraceLogManager

[KishanPRao]

Summary

ToSourceCode() reads the log queue without the lock that Enqueue()/Dequeue() use, so a concurrent log from a background thread could corrupt the read. This makes the manager thread-safe on its own instead of relying on the caller to lock.

Changes

• BacktraceLogManager: Wrap the LogQueue read in ToSourceCode() with lockObject.

ref: BT-7318

[melekr]

Non-blocking: the lock scope could be narrowed to only the ToArray() copy, then build the StringBuilder after releasing the lock. Still looks good given the small default log count, but the narrower scope would be cleaner.

[KishanPRao]

Non-blocking: the lock scope could be narrowed to only the ToArray() copy, then build the StringBuilder after releasing the lock. Still looks good given the small default log count, but the narrower scope would be cleaner.

Good idea, I've narrowed the lock's scope.