[maps-ios][maps-android] Expose line cutout opacity and width (#5884)

This PR expose experimental `LineLayer.lineCutoutOpacity` and
`LineLayer.lineCutoutWidth` and showcases usage in dynamic view
annotation example.

| iOS | Android |
|--------|--------|
| <img width="300" alt="Screenshot 2025-08-15 at 12 57 07"
src="https://github.com/user-attachments/assets/b956f04a-80c3-41fe-944b-9e53a59adcb3"
/> | <img width="300" alt="Screenshot_1755251828"
src="https://github.com/user-attachments/assets/c544a18d-6a72-4590-b120-67013bf41d8c"
/> |

Addresses: https://mapbox.atlassian.net/browse/MAPSAND-2292 and
https://mapbox.atlassian.net/browse/MAPSIOS-1948

cc @mapbox/maps-ios
cc @mapbox/maps-android

---------

Co-authored-by: Ramon <[email protected]>
GitOrigin-RevId: f264ec16c9acbad90e8115d429652bfac73179bc

Author: 2 people

CHANGELOG.md

@@ -10,6 +10,7 @@ Mapbox welcomes participation and contributions from everyone.
 ## 11.15.0-beta.2 - 15 August, 2025
 
 * Add configuration option to configure attribution button tint color.
+* Expose `LineLayer.lineCutoutOpacity` and `LineLayer.lineCutoutWidth` to make route lines visible through obstructing 3D buildings and other aboveground features.
 
 ## 11.15.0-beta.1 - 12 August, 2025
 

Sources/Examples/All Examples/Annotations/DynamicViewAnnotationExample.swift

@@ -296,6 +296,9 @@ private final class Route {
         routeLayer.lineBorderWidth = .constant(2)
         routeLayer.lineBorderColor = .expression(colorExpression(normal: "#666666", selected: "#327AC2"))
         routeLayer.slot = .middle
+        // make route lines visible through obstructing 3D buildings and other aboveground features
+        routeLayer.lineCutoutWidth = .constant(30)
+        routeLayer.lineCutoutOpacity = .constant(0.2)
         try! mapView.mapboxMap.addLayer(routeLayer)
 
         // Annotation