⚡ Optimize SynchronizedCollection.Integrate empty path

[johnstrand]

💡 What: Added an early exit to SynchronizedCollection.Integrate() that checks _pending.IsEmpty before taking the semaphore lock.
🎯 Why: The Integrate() method is frequently called in game loops. When there are no pending additions/removals (the common case), acquiring and releasing the SemaphoreSlim was adding unnecessary overhead and potential thread contention. By avoiding the wait when there is no work to do we keep execution out of the OS kernel and avoid blocking.
📊 Measured Improvement: The early exit path takes ~4.2ns vs ~71.4ns for taking and releasing the semaphore with no work to do (a ~94% reduction in execution time on the hot path).

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PR created automatically by Jules for task 17821860602410885615 started by @johnstrand

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