⚡ Bolt: [performance improvement] Add sync.Pool for response writer buffers

[rschumann]

💡 What: Added sync.Pool to reuse bytes.Buffer in ResponseWriterWrapper.
🎯 Why: Every API request was allocating a new bytes.Buffer to capture the response body for logging, causing unnecessary GC pressure and memory allocations in the hot path.
📊 Impact: Significantly reduces per-request allocations for the API gateway.
🔬 Measurement: Go benchmarks show reduced memory allocations when initializing and using the response writer wrapper.

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PR created automatically by Jules for task 6709427601771959753 started by @rschumann

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