⚡ Optimize string accumulation in ExtractTopology

[xkilldash9x]

💡 What: Optimized string literal concatenation in ExtractTopology by avoiding intermediate []byte allocations and refactoring the logic into a helper function flattenStringLiterals.
🎯 Why: The previous implementation allocated a new byte slice for each string literal ([]byte(s)), which could be inefficient for functions with many string literals.
📊 Measured Improvement:
Benchmark showed comparable performance (approx 122k ns/op vs 123k ns/op) and identical memory allocation count (1 alloc/op). This indicates the Go 1.24 compiler likely already optimized the []byte(s) conversion in the append context. However, the change makes the code more idiomatic (append(b, s...)) and guarantees zero intermediate allocation regardless of compiler optimization levels. A new benchmark BenchmarkFlattenStringLiterals was added to verify this.

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PR created automatically by Jules for task 5495069235814211934 started by @xkilldash9x

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