MetadataEdit online
DITA has a solid vocabulary for specifying metadata. There are
<prolog> elements in the topics, and
<topicmeta>, <bookmeta> elements in the
bookmaps. They can be used to define authors, dates, audiences, organizations, etc. See: https://www.oxygenxml.com/dita/1.3/specs/archSpec/base/metadata-in-maps-and-topics.html
It is up to you to decide where this information should be presented, in the PDF content or in the PDF document properties.