[TransformContext] Add pinch/zoom gesture

[techniq]

https://www.layerchart.com/docs/components/Transform

Might need to think on how best to opt-in to this (if you're scrolling down the screen, hitting a chart/map and immediately scrolling can be frustrating, especially if there isn't enough of an edge on either side to use to continue to scroll.

Sometimes maps/etc require multiple fingers to active the scrolling, for example.

discussion

[techniq]

Mobile support should be handled when we switch to pointer events (#144) although this issue will be used to improve how it integrates on mobile (opt in, require 2 fingers to drag, etc). Also, implementing pointer-based pinch/zoom gestures instead of relying on mousewheel events

[techniq]

Pointer events implemented and also integrated Transform into Chart as TransformContext.

Still need to implement pinch/zoom gesture