chore: suppress git detached HEAD advice during clone

bootstrap.sh

@@ -84,7 +84,8 @@ TMP_DIR=$(mktemp -d)
 trap 'rm -rf "$TMP_DIR"' EXIT
 
 echo "📥 Cloning ${REPO_URL}@${VERSION} → $TMP_DIR"
-git clone --depth 1 --branch "$VERSION" "$REPO_URL" "$TMP_DIR" >/dev/null
+git -c advice.detachedHead=false \
+  clone --depth 1 --branch "$VERSION" "$REPO_URL" "$TMP_DIR" >/dev/null
 
 # 4 ─ Install git-cliff via helper script ──────
 bash "$TMP_DIR/scripts/install-git-cliff.sh"