Fullscreen mode: first mouse-wheel notch after reversing scroll direction is ignored

Environment: Claude Code 2.1.283, kitty 0.49.0, macOS 27.0 (26A428). Mouse with a notched (non-free-spinning) wheel.

Steps

1. In fullscreen rendering, open a conversation long enough to scroll.
2. Scroll up one wheel notch at a time: each notch scrolls, as expected.
3. Reverse direction and scroll down one notch.

Expected: the first notch in the new direction scrolls.
Actual: the first notch after a reversal does nothing. From the second notch on, it scrolls one-for-one again. Same thing in both directions.

Tried, no effect

• "wheelScrollAccelerationEnabled": false in settings.json: no change.
• /scroll-speed set to whole numbers (1, 3): only changes how many lines each notch scrolls; the first reversed notch is still dropped.

The terminal delivers the event
In a plain kitty window with SGR mouse reporting on (printf '\e[?1000h\e[?1006h'; cat -v), every notch prints one wheel escape sequence, including the first notch after reversing, in both directions. So kitty sends the event, and Claude Code's wheel handling drops it (possibly leftover scroll state or a direction-change debounce).

Outside Claude Code, kitty's own scrollback also reverses cleanly.