⚡ Avoid redundant vector allocation in EntityManager

[google-labs-jules]

💡 What

Optimized EntityManager::getTransforms to avoid allocating a new std::vector<Transform> every frame.

🎯 Why

Allocating memory in the main render loop is expensive and causes heap fragmentation. By reusing a persistent vector as a cache, we reduce allocator overhead.

📊 Measured Improvement

Benchmark Results:

• Baseline: ~1050us per call (100k entities)
• Optimized: ~1050us per call (100k entities)

Note: The benchmark environment showed high variance, masking the micro-optimization gains. However, this is a standard zero-allocation pattern for high-performance loops. Theoretically, it removes malloc/free cycles for the transforms vector every frame.

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PR created automatically by Jules for task 369316685402116316 started by @TECHNICANGEL

[google-labs-jules]

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