v0.3.0

What's new

• Packed save: notebooks can compress themselves via browser-native gzip. Split save button lets you toggle between normal and packed modes.
• Toolbar badges: signed and packed status shown as badges next to the title.
• Module hygiene: all ES modules are now pure (no side effects). A dedicated globals.js handles all window.* bindings.
• Release notes: update panel now shows release notes when checking for updates.
• Build compression: node build.js --compress produces a self-extracting packed build.

Fixes

• Fixed multi-line imports not stripped by build script.
• Fixed cross-module imports (notifyDirty, S in init, setBadge).
• Converted inline window.X definitions in keyboard.js to proper exports.