v2

Adds Codeforces support via a per-site adapter pattern.
Storage moved to IndexedDB, centralized in the background service worker so notes are shared across sites instead of siloed per-origin. Autosave with debounced save-on-pause and a live unsaved/saved indicator.
Panel is now draggable, resizable, and collapsible (collapsed by default), with a keyboard shortcut (Alt+L) to toggle it.

Full Changelog: v1...v2