perf(query): pre-size mergedList in merge()#9721
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The @normalize merge appends exactly one node per (parent,child) pair, so the final length is len(parent)*len(child). Pre-sizing avoids grow-and-copy. The capacity is capped at x.Config.LimitNormalizeNode: the loop bails out once the node count exceeds that limit, so without the cap a large normalize query that is going to be rejected would still trigger a huge (or integer-overflowing) up-front allocation. BenchmarkMergeNormalize (64x64): allocs/op 25 -> 10 (-60%), time -24%.
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The @normalize merge appends exactly one node per (parent,child) pair, so the final length is
len(parent)*len(child). Pre-sizing avoids grow-and-copy.BenchmarkMergeNormalize(64×64): allocs/op 25→10 (-60%), time -24%.Independent change; branched from
4b9b399d. Verified: package unit tests pass + Go benchmark (benchstat, p<0.01). Single-thread microbenchmarks; not yet run through the Docker integration suite.