Accurate constraints on alternate-projected maps

[mourner]

On certain alternate projections + low zoom combinations, map constraints are not accurate. For example, on this view of Albers, you can't pan the map down to see southern part of South America:

We should fix this so that you can always pan to see any fraction of the world on any projection.

[karimnaaji]

An example where this was also noticed:

• https://personal.tcu.edu/kylewalker/maps/education/#4.5/38.92/-118.72

https://user-images.githubusercontent.com/7061573/139752534-400ca8b6-a0b6-41f5-a376-362f2ff8015e.mov

[SnailBones]

I'm noticing issues with zoom constraints with a high center latitude and high parallel latitudes on conic projections. In this case I can pan across the whole map, but I can't zoom out to see more than a fraction of it.

This seems to be a pretty minor issue, since it can be fixed by setting a lower center latitude, which makes the map smaller.