Get roadmap issues

curl -X GET "https://app.dacard.ai/api/roadmap/issues?productId=prod_abc" \
  -H "Authorization: Bearer $DACARD_API_KEY"

{
  "byFunction": {
    "design": [
      { "id": "lin_abc", "title": "...", "state": "in_progress", "url": "..." }
    ],
    "development": [...]
  }
}