feat: add phase 2 bun_install repository rule bootstrap

tests/install_test/stale_lockfile.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+bun_path="$1"
+workdir="$(mktemp -d)"
+trap 'rm -rf "${workdir}"' EXIT
+
+cat > "${workdir}/package.json" <<'JSON'
+{
+  "name": "stale-lockfile-test",
+  "version": "1.0.0"
+}
+JSON
+
+"${bun_path}" install --cwd "${workdir}" >/dev/null
+
+cat > "${workdir}/package.json" <<'JSON'
+{
+  "name": "stale-lockfile-test",
+  "version": "1.0.0",
+  "dependencies": {
+    "left-pad": "1.3.0"
+  }
+}
+JSON
+
+set +e
+output="$(${bun_path} install --cwd "${workdir}" --frozen-lockfile 2>&1)"
+code=$?
+set -e
+
+if [[ ${code} -eq 0 ]]; then
+  echo "Expected frozen lockfile install to fail when package.json changes" >&2
+  exit 1
+fi
+
+if [[ "${output}" != *"lockfile"* && "${output}" != *"frozen"* ]]; then
+  echo "Expected lockfile-related error, got:" >&2
+  echo "${output}" >&2
+  exit 1
+fi