Session artifact pills - Make the pills responsive with an overflow pill when it can't them all

Current: Shows a horizontal scrollbar when there's too many pills in a row. This is hard to navigate and pills could be missed out.

Proposal: Use a special pill for overflow items, that shows at the end. Any pill that cannot it in the row, gets rolled into the overflow. Use the same structure as that of "artifacts" pill that creates separate sections for various types.

[Needs design to finalize approach]