Selection options applied when defining it, not changeable afterwards

Nobody has claimed this yet.

## Use case

user realizes the 'selection-extract' or the 'selection-color' is wrong. To realize that, they have already defined the selection pixbuf: sadly, those options are applied at the time of the 'define' operation, so the app expects them to unselect, change the value, and start all over again

## Suggested solution

damn idk, i'm at work i don't have time for this, i'll think about that later

grouping the related selection operations with an id, retroactively change the 'define' operation, and rebuild the selection pixbuf from the history in `on_options_changed`??

### Possible drawbacks

huge change to how the selection works = hard as hell = bugs everywhere

### Possible alternatives

no

Start by tracing the selection-extract and selection-color options through the define operation and on_options_changed. Review how the selection pixbuf and operation history are handled. Done would allow changing these options after defining a selection without requiring the user to unselect and start over, while preserving existing selection behavior.

Written by the indexing model from the issue text.