CSS to reduce upper list margin to paragraphs without changing it in callouts

I think you could use either of these sets to reset lists in callouts (or adjust as desired):

.callout ul { margin-block-start: unset; }
.callout ol { margin-block-start: unset; }

and/or:

.callout li {
    padding-top: unset;
    padding-bottom: unset;
    line-height: unset;
}

.callout :is(ul, ol) {
    margin-top: unset;
    margin-bottom: unset;
}

Give both a try.

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