[Feature] Confirm chunkgen on large generations?

[ianc1215]

Can you add a confirmation dialog that pops up when the amount of chunks exceeds an amount? Basically just way for the game to tell "Hey you are about to generate 15,000 chunks. Are you sure you want to do this?"

Also along with this can you add a command that allows you to calculate how many chunks you are about to generate. Like the same thing as above but a command like "chunkgen calculate radius ~ ~ 50 0". Have the command tell you that will be ### chunks.