fix(library): PageUp/PageDown in note editor no longer scrolls the block off screen - #51

Summary

PageUp/PageDown in the notes editor could shift the whole block up until its top edge was off screen. When the textarea can't scroll further, the browser chains the page key to the nearest scrollable ancestor, and an overflow:hidden ancestor (the block) still scrolls programmatically. The editor now records its ancestors' scroll positions on those keys and restores them if they move (for 250 ms after the key).

Status

Cause inferred from the symptom and the layout; not reproduced without the running app.

Routes

Purely a local UI fix in the editor; identical on plain-SSH and wsh hosts (host notes and general notes share the editor).

Test plan

• Notes editor with a long note: PageDown/PageUp scrolls the text, the block's top edge stays put
• PageDown at the end of the note and PageUp at the start: block does not move
• Short note (no textarea scrolling): same
• Host Inspector note card (compact editor): same
• Mouse wheel and scrollbars still work everywhere

npx vitest run passes; prettier clean; tsc unchanged (16 pre-existing errors).

🤖 Generated with Claude Code

https://claude.ai/code/session_01W6QMXXvRReaKxWk1JL5Et6