Req: Only AND_* after or before x step

[torridgristle]

SD WebUI has a prompt editing feature for changing the prompt depending on the step. I would like to be able to confine AND_PERP / AND_SALT to only some steps at the start or end in a similar way, though it doesn't seem possible at the moment.

[ljleb]

Not possible ATM. I intend to merge this extension with prompt fusion at some point. This will allow to interpolate different noises together in a similar way the conditionings are, which is a superset of the requested feature.