[css-color-hdr][editorial] Update changes

Author: svgeesus

css-color-hdr-1/Overview.bs

@@ -1839,7 +1839,8 @@ in a user stylesheet.
 	</a></h3>
 
 <ul>
-	<!-- to 18 July 2025 -->
+	<!-- to 19 July 2025 -->
+	<li>Added the clamp function which is used in  hdr-color() </li>
 	<li>Added sample code for hdr-color()</li>
 	<li>Explained where the eps factor comes from, and what it is for 
 		(<a href="https://github.com/w3c/csswg-drafts/issues/11788">#11788</a>)</li>