QC cache thread level memory limit uses the global memory limit

During startup MaxScale reports the amount of memory that each thread would use for the query classification results.

2026-01-22 16:26:32   notice : Query classification results are cached and reused. Maximum memory used per thread: 596.29MiB, in total: 4.65GiB.

The per thread value is what the threads should be using but in reality the threads end up using the total value. This results in excessive memory usage for workloads which do not fit into the cache.