Add numa_nodes parameter to BaseMoEWrapper and all subclasses, allowing
users to explicitly specify which NUMA node IDs to use for subpool
mapping instead of always defaulting to sequential [0, 1, ..., N-1].
This enables running multiple KTransformers instances on different NUMA
nodes of the same machine, e.g. --kt-threadpool-count 1 --kt-numa-nodes 1
to bind to NUMA node 1. Previously this required external numactl
workarounds since subpool_numa_map was hardcoded to start from 0.