[main] feat(moe): Support moe shared expert gate for Qwen3-Next (2/4)#2751

Phlip79 merged 3 commits intoNVIDIA:mainNVIDIA/Megatron-LM:mainfrom

yuzhongw-nvidia:shared_expert_gateyuzhongw-nvidia/Megatron-LM:shared_expert_gateCopy head branch name to clipboard