iOS: Left-edge swipe should return to previous page, not open menu

Currently the iOS left-edge swipe opens the side menu (Home). I'd suggest binding it to "go back to the previous page" instead.

Why this matters:

• The "<" back button sits at the very top and is hard to reach one-handed
• Home already lives on the bottom bar right under the thumb, so the edge-swipe-to-menu just duplicates a reachable action
• The genuinely useful action — stepping back between pages/notes — currently has no gesture at all
• Two adjacent gestures doing nearly the same thing, while the useful one is missing

Ideal: re-bind the left-edge swipe to "back." Configurable would be even better, so users can choose.

iOS 18.6, Capacities 1.66.1