Fix two editor input bugs:
1. Arrow key cursor movement not visually updating (fixes#464)
The layout cache key only included {width, textVersion}. Cursor-only
moves don't change textVersion, so stale cached layout was returned
and the diff renderer skipped repaint. Added cursorLine and cursorCol
to the cache key so cursor movements invalidate the cache.
2. Shift+Enter not inserting newlines in non-kitty terminals (Zed, VS Code, etc.)
The /terminal-setup command configures terminals to send ESC+CR (\x1b\r)
for Shift+Enter. But the followUp app action (bound to alt+enter) was
intercepting \x1b\r in CustomEditor.handleInput before the editor's
newLine handler could see it — because in non-kitty terminals, \x1b\r
matches alt+enter. Now when kitty protocol is not active and \x1b\r is
received, the followUp match is skipped so it falls through to newLine.
Alt+Enter followUp still works in kitty-protocol terminals (iTerm2,
Ghostty, Kitty, WezTerm) where the key combos are distinguishable.
Co-authored-by: TÂCHES <afromanguy@me.com>
6d84d1c317