[css-gaps-1] Clarify that no decorations are drawn next to fragment breaks

Author: kbabbitt

css-gaps-1/Overview.bs

@@ -241,6 +241,11 @@ Layout and painting</h3>
 		multicol/multicol-gap-decorations-024.html
 	</wpt>
 
+	[[css-align-3#column-row-gap]] specifies that gaps disappear
+	where they coincide with a [=fragmentation break=].
+	Because there is no gap in such locations,
+	no [=gap decoration=] is drawn in them either.
+
 	<wpt>
 		flex/fragmentation/flex-gap-decorations-fragmentation-001.html
 		flex/fragmentation/flex-gap-decorations-fragmentation-002.html
@@ -1565,4 +1570,5 @@ Changes since the <a href="https://www.w3.org/TR/2025/WD-css-gaps-1-20250417/">1
 			(<a href="https://github.com/w3c/csswg-drafts/issues/12603">Issue 12603</a>,
 			<a href="https://github.com/w3c/csswg-drafts/issues/12848">Issue 12848</a>,
 			<a href="https://github.com/w3c/csswg-drafts/issues/8402">Issue 8402</a>)
+		<li>Added a paragraph clarifying that gap decorations are not drawn where gaps are suppressed due to fragment breaks.
 	</ul>