Show/Calculate nuke flux targets/calculate optimal target

[AHeroicLlama]

https://discord.com/channels/1029499482028646400/1029507878261899386/1238338442455420998

We would like a way to place a nuke circle on the map, to show which fluxes would be generated within it. Additionally, it would be good if we could auto calculate the optimal nuke placement for each (including combinations of) flux colours.