fix(pmd): use atomic rename to avoid concurrent extraction conflicts

Extract to a temporary directory first, then atomically move into place.
This prevents parallel prek processes from contending over partial extractions
and hitting unzip errors when the destination already exists.

Author: Goldziher

hooks/pmd/run.sh

@@ -33,9 +33,15 @@ if [[ ! -x "${pmd_launcher}" ]]; then
     printf 'pmd: `unzip` not available; install it to extract the pmd distribution.\n' >&2
     exit 1
   fi
-  mkdir -p "${extract_dir}"
-  unzip -q -o -d "${extract_dir}" "${archive_path}"
-  chmod +x "${pmd_launcher}"
+  # Extract to a temporary directory first, then move atomically.
+  # This prevents concurrent extraction processes from conflicting.
+  temp_extract_dir="${extract_dir}.$$-${RANDOM}"
+  mkdir -p "${temp_extract_dir}"
+  unzip -q -d "${temp_extract_dir}" "${archive_path}"
+  chmod +x "${temp_extract_dir}/pmd-bin-${VERSION}/bin/pmd"
+  # Atomic rename (only one process will succeed).
+  mkdir -p "$(dirname "${extract_dir}")"
+  mv -f "${temp_extract_dir}" "${extract_dir}" || rm -rf "${temp_extract_dir}" 2>/dev/null || true
 fi
 
 # Make the launcher pick up our verified JDK.