fix(tui): add vertical scrolling to Editor when content exceeds terminal height

The Editor component now accepts TUI as the first constructor parameter,
enabling it to query terminal dimensions. When content exceeds available
height, the editor scrolls vertically keeping the cursor visible.

Features:
- Max editor height is 30% of terminal rows (minimum 5 lines)
- Page Up/Down keys scroll by page size
- Scroll indicators show lines above/below: ─── ↑ 5 more ───

Breaking change: Editor constructor signature changed from
  new Editor(theme)
to
  new Editor(tui, theme)

fixes #732

packages/tui/CHANGELOG.md

@@ -2,6 +2,18 @@
 
 ## [Unreleased]
 
+### Breaking Changes
+
+- `Editor` constructor now requires `TUI` as first parameter: `new Editor(tui, theme)`. This enables automatic vertical scrolling when content exceeds terminal height. ([#732](https://github.com/badlogic/pi-mono/issues/732))
+
+### Added
+
+- Editor now supports Page Up/Down keys (Fn+Up/Down on MacBook) for scrolling through large content ([#732](https://github.com/badlogic/pi-mono/issues/732))
+
+### Fixed
+
+- Editor no longer corrupts terminal display when text exceeds screen height. Content now scrolls vertically with indicators showing lines above/below the viewport. Max height is 30% of terminal (minimum 5 lines). ([#732](https://github.com/badlogic/pi-mono/issues/732))
+
 ## [0.46.0] - 2026-01-15
 
 ### Fixed