[Klaud Cold] [AMD] Bump DSV4 MI355X vLLM 8k/1k to the 2026-09-01 nightly / [Klaud Cold] [AMD] 将 DSV4 MI355X vLLM 8k/1k 更新至 2026-09-01 nightly (#2792)

* perf(dsv4): bump MI355X 8k1k vLLM nightly

Update the fixed-sequence STP and MTP image pins to the 2026-09-01 ROCm nightly. Keep the existing AITER flags because the newly merged DSV4 optimizations auto-enable through that path.

中文：将 MI355X 固定序列 8k/1k 的 DSV4 STP 与 MTP 镜像更新到 2026-09-01 ROCm nightly。保留现有 AITER 标志，新合入的 DSV4 优化会通过该路径自动启用。

* perf(dsv4): trigger MI355X 8k1k nightly sweep

Append the fixed-sequence STP and MTP image update to the performance changelog for PR #2792.

中文：在性能变更日志末尾追加 PR #2792 的固定序列 STP/MTP 镜像升级条目，以触发基准测试扫描。

* perf(dsv4): enable ROCm recipe flags

Add shared-expert fusion and INT4 quick-reduce environment variables to the MI355X 8k/1k STP and MTP paths, and document the explicit recipe settings.\n\n中文：为 MI355X 8k/1k 的 STP 与 MTP 路径加入 shared-expert fusion 和 INT4 quick-reduce 环境变量，并同步记录显式启用的配方设置。

* chore: skip redundant sweep [skip-sweep]

Reuse the completed full sweep after synchronizing the PR with main.

中文：PR 与 main 同步后复用已完成的完整扫描，跳过重复扫描。

* chore: refresh PR #2792 for sweep reuse [skip-sweep]

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Co-authored-by: Jiahui Cao <jiacao@crs-m2m-cpu-spur-012.us-east2-a.compute.internal>
Co-authored-by: Chun Fang <chun.fang@amd.com>
Co-authored-by: functionstackx <47992694+functionstackx@users.noreply.github.com>