Fix: Limit the sorting files based on max_compaction_jobs instead of kNumberFilesToSort to reduce write amplification

[ProtoYun]

PR #10161 improves compaction performance by using a partial‑sorting mechanism that operates on a fixed number of files (kNumberFilesToSort). However, when the number of concurrent background compaction jobs exceeds kNumberFilesToSort, this strategy causes write amplification. The fix selects sorting files according to the max_compaction_jobs setting in order to mitigate write amplification and keep the performance.

Benchmarks with db_bench fillrandom demonstrate that, when max_compaction_jobs is configured to 128, write amplification is reduced by 25 % without performance degradation.

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