Feature

(Split off from #3001)

Add the ability to have multiple table headers / footers that are not necessarily at the top / bottom of the table.

This would work by having the header row start being repeated until the end, or until the next header, once it's reached. Similarly, the footer is repeated from the start (or once the previous footer is reached) until its row is actually reached in the main table layout.

Goal

This would allow for some simple table section functionality. See also ConTeXt's table sections for some inspiration: https://wiki.contextgarden.net/TABLE#Multipage_TABLEs

We could optionally use this in the syntax (section) or just allow for multiple headers / footers anyway (simpler in principle, but maybe not ideal semantically).