[DevTask] Support usage on Mobile

[huchenlei]

#35 reported that the editor is unusable on mobile devices (Phone, Tablet). I think add a button to control the zoom/pan mode is only part of the solution for the extension to be fully usable on mobile.

There are several things to do to make the editor usable on mobile:

• The modal should take more screen space
• The left panel should be foldable (Drawer)
• 2 finger pinch should zoom in/out the canvas
• drag on canvas should pan the canvas
• In selection mode, keypoints should be bigger for easier selection and drag.

[lybmccree]

Thank you