[ios][home] Add three finger gesture to open the dev menu + some refactoring (#7891)

# Why

Fixes #7644 and brings us closer to the separate `expo-dev-menu` package that can live without kernel.

[ios][home] Add three finger gesture to open the dev menu + some refactoring (#7891)

# Why

Fixes #7644 and brings us closer to the separate `expo-dev-menu` package that can live without kernel.
Also fixed https://twitter.com/bantingGamer/status/1251154340129062917

# How

- Added `EXDevMenuManager` singleton that manages the dev menu. Most parts of it were in kernel or some others classes strongly connected with kernel. Now, kernel is just its delegate.
- Refactored `EXKernelDevMotionHandler` to `EXDevMenuMotionInterceptor` which is much clearer and makes it possible to uninstall the interceptor (these interceptors are kinda hacky, I tried not to do them this way but well, RN does the same ��).
- Added `EXDevMenuGestureRecognizer` for long press gesture, with minimum press duration set to 0.5s and with light impact haptic feedback.
- Added `EXDevMenuGestureInterceptor` that swaps the default implementation of `UIView#gestureRecognizers`, but only for `UIWindow`s. This is needed to make three-finger gesture work everywhere in the app.
- Renamed `EXMenuViewController` to `EXDevMenuViewController` (all dev menu classes should be prefixed by `EXDevMenu`) and again, removed some connections to kernel.
- Added UI in user settings to select dev menu gestures (can select them separately).
- Fixed an issue with dev menu view being below modals in the view hierarchy.

# Test Plan

So far I've tested it only with published experience. I'm gonna do smoke tests on dev apps later.
I mostly focused on testing whether:
- the dev menu works in general (after refactoring)
- three-finger gesture works on the initial screen of the app, on the modals and on the dev menu itself
- all combinations of selected gestures work as expected
- selected gestures persist after killing and relaunching the client

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