2594d5f7

By: Michael Lynch <git@mtlynch.io>

Extract swipe gestures into shared helper

Move the media page's touch tracking into a reusable browser helper that
emits swipeLeft and swipeRight events from any element marked with the
shared data attribute.

Add node:test coverage for the helper and run those tests from
check-frontend so the behavior stays covered in the normal frontend
validation path.