feat: trigger on issues opened when @cursor in title or body

Extend check-comment.sh to parse issues event payloads; document
issue_comment + issues opened as supported workflow triggers.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/check-comment.sh

@@ -15,14 +15,18 @@ fi
 
 OUTPUT_FILE="${GITHUB_OUTPUT:?GITHUB_OUTPUT is not set}"
 
-COMMENT_BODY=$(jq -r '
+COMMENT_BODY=$(jq -r \
+  --arg event_name "${GITHUB_EVENT_NAME:-}" \
+  '
   if .comment?.body? then .comment.body
   elif .review?.body? then .review.body
+  elif $event_name == "issues" then
+    ((.issue.title // "") + "\n" + (.issue.body // ""))
   else empty end
-' "$EVENT_FILE")
+  ' "$EVENT_FILE")
 
 if [ -z "$COMMENT_BODY" ]; then
-  echo "No comment or review body in event payload — skipping."
+  echo "No @cursor trigger text in event payload — skipping."
   echo "run_cursor=false" >> "$OUTPUT_FILE"
   exit 0
 fi
@@ -63,6 +67,11 @@ jq \
         id: .review.id,
         user: (.sender.login // "unknown")
       }
+      elif ($event_name == "issues") and .issue then {
+        body: ((.issue.title // "") + "\n" + (.issue.body // "")),
+        id: null,
+        user: (.sender.login // .issue.user.login // "unknown")
+      }
       else null end
     ),
     issue: {