Copy an object (or range) to a new location.
``source`` and ``target`` accept grandMA2 selection expressions: a single ID
or a range/list using thru / + / - (e.g. "1 thru 10", "1 + 3 + 5"), so a
whole range copies in one call.
Args:
object_type: Object type ("cue", "preset", "group", "sequence", "macro", ...)
source: Source selection expression
target: Target selection expression
mode: "default", "overwrite", or "merge"
Returns:
str: Operation result message
Examples:
- Copy cue 1 to cue 10: object_type="cue", source="1", target="10"
- Copy groups 1 thru 5 to 11: object_type="group", source="1 thru 5", target="11"