In rollup, we don't have object syntax like foo=bar,qux=baz, instead, we use : and , to create objects. Consider aligning this part with rollup in the future. any suggestions? cc @sapphi-red

Originally posted by @h-a-n-a in #8551 (comment)

Currently, in rolldown, --global flag is actually using key=value syntax, however, in rollup it uses key:value pair.