Optimize large point clouds

[emilk]

What

This saves us a lot of time, with less code :)

Basically: if we have colors for all our points, then we can ignore the annotation contexts. Before we ignored them once for each point, now we ignore them all in one go.

I also added a happy path for position/radii

opf before

opf after

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[Wumpf]

noice :chefkiss: