Replace intro image with maps-intro screenshot

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: torimwhaley

references/chart-types/map.mdx

@@ -10,7 +10,7 @@ icon: "earth-europe"
   </Card>
 </a>
 
-![map](/images/references/chart-types/map/map-chart.png)
+![map](/images/references/maps-intro.png)
 
 <Info>
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