Reject Conventional Commit PR titles

Authored-By: Codex (GPT-5) <noreply@openai.com>

check.sh

@@ -121,6 +121,12 @@ if echo "${TITLE}" | grep -qE "^\[bug-[a-z0-9]+\] ."; then
   TITLE_BUG=$(echo "${TITLE}" | sed -E 's|^\[(bug-[a-z0-9]+)\].*|\1|')
 fi
 
+TITLE_DESCRIPTION=$(printf '%s\n' "${TITLE}" | sed -E 's/^\[bug-[a-z0-9]+\] //')
+if printf '%s\n' "${TITLE_DESCRIPTION}" | grep -qE '^[[:alnum:]-]+(\([^)]*\))?!?:[[:space:]]'; then
+  echo "FAIL[check-naming]: title must use a plain-language imperative without Conventional Commit syntax"
+  FAILED=1
+fi
+
 if [ "${BRANCH_KIND}" = "role-bug" ]; then
   if [ -z "${TITLE_BUG}" ]; then
     echo "FAIL[check-naming]: title must lead with [${BRANCH_BUG}]"