Add a new option "title" during a PDF export

Currently, the title used by the PDF export is the doc.title.
It could be interesting to be able to choose a specific title for this specific export.

Context: On a daily basis, I create documents with a specific title that allows me to find my document faster and easier like [Project version] Type - summary. The issue is, when I want to export this document, I often want a different title, with the summary only, or a different one depending on who will receive it.

As the PDF export allows options: cover, table of contents, comments and image attachments, a different title could be added to this list of options.