Add Burrow forge infrastructure and tailnet control plane

Scripts/_burrow-flake.sh

@@ -0,0 +1,95 @@
+#!/usr/bin/env bash
+
+burrow_require_cmd() {
+  if ! command -v "$1" >/dev/null 2>&1; then
+    echo "missing required command: $1" >&2
+    exit 1
+  fi
+}
+
+burrow_cleanup_flake_tmpdirs() {
+  if [[ "${#BURROW_FLAKE_TMPDIRS[@]}" -eq 0 ]]; then
+    return
+  fi
+  rm -rf "${BURROW_FLAKE_TMPDIRS[@]}"
+}
+
+burrow_prepare_flake_ref() {
+  local input="${1:-.}"
+
+  case "${input}" in
+    path:*|git+*|github:*|tarball+*|http://*|https://*)
+      printf '%s\n' "${input}"
+      return 0
+      ;;
+  esac
+
+  local resolved
+  resolved="$(cd "${input}" && pwd)"
+
+  local cache_root="${HOME}/.cache/burrow"
+  mkdir -p "${cache_root}"
+
+  local copy_root
+  copy_root="$(mktemp -d "${cache_root}/flake-XXXXXX")"
+  mkdir -p "${copy_root}/repo"
+
+  rsync -a \
+    --delete \
+    --exclude '.git' \
+    --exclude '.direnv' \
+    --exclude 'result' \
+    --exclude 'burrow.sock' \
+    --exclude 'node_modules' \
+    --exclude 'target' \
+    --exclude 'build' \
+    "${resolved}/" "${copy_root}/repo/"
+
+  BURROW_FLAKE_TMPDIRS+=("${copy_root}")
+  printf 'path:%s/repo\n' "${copy_root}"
+}
+
+burrow_resolve_image_artifact() {
+  local store_path="$1"
+
+  if [[ -f "${store_path}" ]]; then
+    printf '%s\n' "${store_path}"
+    return 0
+  fi
+
+  if [[ -d "${store_path}" ]]; then
+    local candidate
+    candidate="$(
+      find "${store_path}" -type f \
+        \( -name '*.raw' -o -name '*.raw.*' -o -name '*.img' -o -name '*.img.*' \) \
+        | sort \
+        | head -n1
+    )"
+    if [[ -n "${candidate}" ]]; then
+      printf '%s\n' "${candidate}"
+      return 0
+    fi
+  fi
+
+  echo "unable to locate disk image artifact under ${store_path}" >&2
+  exit 1
+}
+
+burrow_detect_compression() {
+  local artifact="$1"
+
+  case "${artifact}" in
+    *.bz2)
+      printf 'bz2\n'
+      ;;
+    *.xz)
+      printf 'xz\n'
+      ;;
+    *.zst|*.zstd)
+      printf 'zstd\n'
+      ;;
+    *)
+      printf '\n'
+      ;;
+  esac
+}