chore: import upstream snapshot with attribution

scripts/install-zig.sh

@@ -0,0 +1,75 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+version="${ZERO_ZIG_VERSION:-0.14.1}"
+release_tag="${ZERO_ZIG_RELEASE_TAG:-toolchain-zig-${version}}"
+mirror_base="${ZERO_ZIG_MIRROR_BASE:-https://github.com/vercel-labs/zerolang/releases/download/${release_tag}}"
+cache_root="${ZERO_ZIG_CACHE_DIR:-${PWD}/.zero/toolchains}"
+
+host_os="$(uname -s)"
+host_arch="$(uname -m)"
+
+case "${host_os}:${host_arch}" in
+  Linux:x86_64)
+    platform="x86_64-linux"
+    archive_name="zig-x86_64-linux-${version}.tar.xz"
+    archive_sha="24aeeec8af16c381934a6cd7d95c807a8cb2cf7df9fa40d359aa884195c4716c"
+    ;;
+  Darwin:arm64 | Darwin:aarch64)
+    platform="aarch64-macos"
+    archive_name="zig-aarch64-macos-${version}.tar.xz"
+    archive_sha="39f3dc5e79c22088ce878edc821dedb4ca5a1cd9f5ef915e9b3cc3053e8faefa"
+    ;;
+  Darwin:x86_64)
+    platform="x86_64-macos"
+    archive_name="zig-x86_64-macos-${version}.tar.xz"
+    archive_sha="b0f8bdfb9035783db58dd6c19d7dea89892acc3814421853e5752fe4573e5f43"
+    ;;
+  *)
+    echo "unsupported Zig host for pinned installer: ${host_os}:${host_arch}" >&2
+    exit 1
+    ;;
+esac
+
+install_dir="${ZERO_ZIG_INSTALL_DIR:-${cache_root}/zig-${version}-${platform}}"
+archive_path="${cache_root}/${archive_name}"
+archive_url="${mirror_base}/${archive_name}"
+
+check_sha256() {
+  expected="$1"
+  path="$2"
+  if command -v sha256sum >/dev/null 2>&1; then
+    printf '%s  %s\n' "$expected" "$path" | sha256sum -c -
+  else
+    printf '%s  %s\n' "$expected" "$path" | shasum -a 256 -c -
+  fi
+}
+
+if [ -x "${install_dir}/zig" ] && [ "$("${install_dir}/zig" version)" = "$version" ]; then
+  echo "Zig ${version} already installed at ${install_dir}"
+else
+  mkdir -p "$cache_root"
+  if [ ! -f "$archive_path" ] || ! check_sha256 "$archive_sha" "$archive_path" >/dev/null 2>&1; then
+    echo "Downloading ${archive_name} from repo mirror"
+    curl -fsSL --retry 3 --retry-delay 2 --output "$archive_path" "$archive_url"
+  fi
+  check_sha256 "$archive_sha" "$archive_path"
+
+  tmp_dir="${install_dir}.tmp.$$"
+  rm -rf "$tmp_dir"
+  mkdir -p "$tmp_dir"
+  tar -xf "$archive_path" -C "$tmp_dir" --strip-components=1
+  rm -rf "$install_dir"
+  mv "$tmp_dir" "$install_dir"
+fi
+
+if [ "$("${install_dir}/zig" version)" != "$version" ]; then
+  echo "installed Zig version does not match ${version}: $("${install_dir}/zig" version)" >&2
+  exit 1
+fi
+
+if [ -n "${GITHUB_PATH:-}" ]; then
+  printf '%s\n' "$install_dir" >> "$GITHUB_PATH"
+fi
+
+echo "Zig ${version} installed at ${install_dir}"