Rule renders a horizontal separator line.
Rule is horizontal-only.
new VStack(
"Section A",
new Rule(),
"Section B");
Rule can optionally render labels:
new Rule()
.StartLabel("Left")
.CenterLabel("Center")
.EndLabel("Right");
HorizontalAlignment = Align.Stretch, VerticalAlignment = Align.StartRuleStyle controls line glyphs and label padding.