ref(upstream): FULL TREE — Deep-Spark xllm (1470) + ds_vllm csrc/models (703)

Replaces cherry-picked upstream_ref with complete source trees.

xllm/ — Iluvatar official C++ inference engine (15MB, 1470 files)
  Complete: kernels → layers → models → runtime → scheduler → api
  Excluded: .git, binary images, third_party submodule checkouts

ds_vllm/ — Iluvatar official vllm fork (8MB, 703 files)
  Included: csrc/ (ALL CUDA kernels), fused_moe/, qwen3_5 model, _custom_ops
  Excluded: tests, benchmarks, docs, examples (not needed for reference)

Critical call chains now fully traceable:
  MoE: moe_topk_softmax_kernels.cuh → ixformer.h → fused_moe.cpp → layer
  GDN: qwen3_gated_delta_net_base.cpp → qwen3_5_gated_delta_net.cpp
  Attention: ixformer.h → xllm_paged_attention → attention.cpp

upstream_ref/xllm/.agents/skills/git-workflow/scripts/collect_git_context.sh

@@ -0,0 +1,104 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+mode="auto"
+
+if [[ $# -gt 1 ]]; then
+  echo "usage: $0 [--staged|--all|--unstaged]" >&2
+  exit 1
+fi
+
+if [[ $# -eq 1 ]]; then
+  case "$1" in
+    --staged)
+      mode="staged"
+      ;;
+    --all)
+      mode="all"
+      ;;
+    --unstaged)
+      mode="unstaged"
+      ;;
+    *)
+      echo "unknown option: $1" >&2
+      echo "usage: $0 [--staged|--all|--unstaged]" >&2
+      exit 1
+      ;;
+  esac
+fi
+
+if ! git rev-parse --show-toplevel >/dev/null 2>&1; then
+  echo "not inside a git repository" >&2
+  exit 1
+fi
+
+repo_root="$(git rev-parse --show-toplevel)"
+cd "$repo_root"
+
+staged_count="$(git diff --cached --name-only | wc -l | tr -d ' ')"
+untracked_files="$(git ls-files --others --exclude-standard)"
+
+if [[ "$mode" == "auto" ]]; then
+  if [[ "$staged_count" != "0" ]]; then
+    mode="staged"
+  else
+    mode="all"
+  fi
+fi
+
+case "$mode" in
+  staged)
+    status_cmd=(git diff --cached --name-status)
+    stat_cmd=(git diff --cached --stat)
+    patch_cmd=(git diff --cached --unified=1 --no-color)
+    headline="staged changes"
+    ;;
+  unstaged)
+    status_cmd=(git diff --name-status)
+    stat_cmd=(git diff --stat)
+    patch_cmd=(git diff --unified=1 --no-color)
+    headline="unstaged changes"
+    ;;
+  all)
+    headline="all local changes"
+    ;;
+  *)
+    echo "invalid mode: $mode" >&2
+    exit 1
+    ;;
+ esac
+
+echo "repo: $repo_root"
+echo "branch: $(git branch --show-current)"
+echo "scope: $headline"
+echo
+echo "status:"
+git status --short
+echo
+
+if [[ -n "$untracked_files" ]]; then
+  echo "untracked files:"
+  printf '%s\n' "$untracked_files"
+  echo
+fi
+
+if [[ "$mode" == "all" ]]; then
+  echo "changed files:"
+  git diff HEAD --name-status
+  echo
+  echo "diff stat:"
+  git diff HEAD --stat
+  echo
+  echo "patch excerpt:"
+  git diff HEAD --unified=1 --no-color | sed -n '1,400p'
+else
+  echo "changed files:"
+  "${status_cmd[@]}"
+  echo
+  echo "diff stat:"
+  "${stat_cmd[@]}"
+  echo
+  echo "patch excerpt:"
+  "${patch_cmd[@]}" | sed -n '1,400p'
+fi