The Overview's full-screen button moved from the page's corner into the
navigation, beside the MG4 logo. A swipe in from the left edge (EdgeSwipe,
unit-tested) brings the navigation back; a faint handle marks the edge.
Sideways swipes no longer change the page: only the navigation does.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LhzAVaUyqcw5PkGjz4mWW6
