⚡ Optimize GenerateTopologyHash allocations

[xkilldash9x]

💡 What:
Optimized GenerateTopologyHash in pkg/detection/engine.go by:

1. Pre-allocating the calls slice to avoid resizing.
2. Replacing strings.Builder and strconv.Itoa inside the loop with a reusable []byte buffer and strconv.AppendInt.

🎯 Why:
The previous implementation allocated a new strings.Builder (and underlying buffer) and multiple strings (via Itoa) for every call signature in the loop. This created significant memory pressure and GC overhead in hot paths.

📊 Measured Improvement:
Benchmark BenchmarkGenerateTopologyHash results:

• Time: ~23% faster (35031 ns/op -> 27030 ns/op)
• Allocations: ~50% reduction (215 allocs/op -> 108 allocs/op)
• Memory: ~28% reduction (12328 B/op -> 8856 B/op)

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PR created automatically by Jules for task 515067491780145595 started by @xkilldash9x

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