Add DSV4 FP4 B200 Dynamo SGLang configuration / 新增 DSV4 FP4 B200 Dynamo SGLang 配置

[RohitNagraj]

Summary

• Add a B200 multinode Dynamo SGLang configuration for DSV4 FP4.
• Add checked-in srt-slurm recipes for the configured 8k/1k disaggregated topologies.
• Configure the B200 launcher with the DSV4 FP4 model path and required preflight handling.

Validation

• Generated all configured sweep combinations successfully.
• Validated the changelog entry.
• Validated launcher shell syntax and recipe/config consistency.

中文说明

• 新增用于 DSV4 FP4 的 B200 多节点 Dynamo SGLang 配置。
• 新增已检入的 srt-slurm recipe，覆盖配置中的 8k/1k 分离式拓扑。
• 配置 B200 启动器，接入 DSV4 FP4 模型路径及所需的预检参数处理。

验证

• 已成功生成全部配置扫描组合。
• 已验证性能变更日志条目。
• 已验证启动器 Shell 语法以及 recipe 与配置的一致性。

[github-actions]

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