icon: Ship updated icon

I've failed to build the new Builder, so I'm only attaching the latest version of the app icon that went through a number of iteration between the designers. It may be a hard nut to swallow coming from a detailed 3D icon, but please consider the whole ecosystem rather than the single icon (Like looking at a typeface rather than a single glyph).

We're obviously open to further iterate on the design. The benefit of the style is that it allows for adjustments.