[Model] Add support for nvidia/Llama-3_3-Nemotron-Super-49B-v1

[kylehh]

Motivation

Add support for nvidia/Llama-3_3-Nemotron-Super-49B-v1

Modifications

Migration nemotron_nas from vllm

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
• For reviewers: If you haven't made any contributions to this PR and are only assisting with merging the main branch, please remove yourself as a co-author when merging the PR.
• Please feel free to join our Slack channel at https://slack.sglang.ai to discuss your PR.

[merrymercy]

Do not add these first. Can you drop all of them?

[kylehh]

Missinglayer class was migrated from vllm implementation, which was created by Nemotron team. Keep it for code consistent and future proof. Do these cause the failure of CI pipeline?

[zhyncs]

@kylehh please rebase. thanks.