MTP (multi-token prediction) speculative decoding was enabled, giving the
910C an unfair decode throughput advantage over the H20 baseline (which
has no MTP). Disable it so the benchmark measures pure model throughput.
- config.env: add DSV4_ENABLE_MTP=0 (default off)
- start_vllm_docker.sh: only add --speculative-config when DSV4_ENABLE_MTP=1