Following #129, we should be able to export to the other formats sb-edit has complete or partial support for.
Some notes:
Infer output type from output file extension .sb3, or -ot sb3 / --output-type sb3, as usual
SB3 conversion (#33) is a normal, complete roundtrip: you input a whole project and get out a whole project, like converting SB3 to Leopard
Overwriting the input SB3 would always probably be a bad idea, but the CLI already has examples of avoiding overwriting. We may want to generally implement a warning like, "Output file must not be input file." rather than the current message "Output file already exists."
Following #129, we should be able to export to the other formats sb-edit has complete or partial support for.
Some notes:
.sb3, or-ot sb3/--output-type sb3, as usual