Scrolling downward with flick gesture freezes then teleports #471

I'm testing this in Ghostty on macOS (as well as on Linux over SSH), using an Apple trackpad with inertial scrolling.

When I scroll downward with a flick gesture (2-finger swipe upward on my machine) above a certain speed, moor scrolls a little bit, freezes and teleports downward, then continues scrolling a little bit more (due to the inertia). However, this does not happen when scrolling upward.

This happens with no options set, and I see nothing interesting in the debug log. I'm not sure how to better explain this than "open a long file and scroll down very fast". I suspect this will be much easier to reproduce with a trackpad than a mouse.

Here's some trace logs, just in case there's something that I haven't noticed.

scroll-down.log (opened the file, one swipe gesture, waited for inertia scrolling to stop, then quit)

scroll-up.log (opened the file, paged downward a few times, swiped up, waited for inertia scrolling to stop, then quit)

If anything else would be useful for debugging (screen recording, asciicast, etc.), please let me know.