⚡ Bolt: Optimize case-insensitive prefix matching to prevent allocations

[callmeradical]

💡 What: Replaced strings.ToLower combined with strings.HasPrefix with a zero-allocation strings.EqualFold approach for case-insensitive exact prefix matching.
🎯 Why: strings.ToLower forces a memory allocation (and potentially a string copy), which is inefficient in hot paths like HTTP response processing where this prefix check runs repeatedly.
📊 Impact: Eliminates a memory allocation per proxy response, reducing garbage collection pressure and execution time.
🔬 Measurement: Verified the optimization by checking that all Go tests pass correctly and the prefix matching operates exactly as before without breaking the SSE protocol.

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PR created automatically by Jules for task 5001404722417353410 started by @callmeradical

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