[MAPS3D-1645] StyleSpec: model source definition (#6204)

This PR extends **style specification** with full definition of **model
source** as well as **model-elevation-reference**.
Groundwork for removal of _non-experimental_ status of model layer
targeted at end of year x.17 gl-js/maps releases (MAPS3D-1645,
MAPS3D-1958).

The actual functionality on
- gl-native side is **already there**
- gl-js side missing features are implemented as part of
#5567.

**Changes in this PR**
- definition of `model source`
- documentation / preparation for style-spec docs in [docs-root
PR](mapbox/subdomain-docs-root#486)
- moved `model-elevation-reference` from gl-native-only to v8.json

> [!NOTE]
> Experimental/private flags are kept until functionality is available
in main.

**Public GL-JS commit message**
<public>Extended style specification with model source
definition.</public>

cc @mapbox/gl-js
cc @mapbox/gl-native

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

---------

Co-authored-by: Ivan Persidskii <[email protected]>
GitOrigin-RevId: 3b7ba4d838b739216a72a833e979dbf5278cc36f

Author: 2 people

extension-compose/api/Release/metalava.txt

@@ -3176,6 +3176,7 @@ package com.mapbox.maps.extension.compose.style.layers.generated {
     field public static final com.mapbox.maps.extension.compose.style.layers.generated.ModelElevationReferenceValue.Companion Companion;
     field public static final com.mapbox.maps.extension.compose.style.layers.generated.ModelElevationReferenceValue DEFAULT;
     field public static final com.mapbox.maps.extension.compose.style.layers.generated.ModelElevationReferenceValue GROUND;
+    field public static final com.mapbox.maps.extension.compose.style.layers.generated.ModelElevationReferenceValue HD_ROAD_MARKUP;
     field public static final com.mapbox.maps.extension.compose.style.layers.generated.ModelElevationReferenceValue SEA;
   }
 

extension-compose/api/extension-compose.api

@@ -2635,6 +2635,7 @@ public final class com/mapbox/maps/extension/compose/style/layers/generated/Mode
 	public static final field Companion Lcom/mapbox/maps/extension/compose/style/layers/generated/ModelElevationReferenceValue$Companion;
 	public static final field DEFAULT Lcom/mapbox/maps/extension/compose/style/layers/generated/ModelElevationReferenceValue;
 	public static final field GROUND Lcom/mapbox/maps/extension/compose/style/layers/generated/ModelElevationReferenceValue;
+	public static final field HD_ROAD_MARKUP Lcom/mapbox/maps/extension/compose/style/layers/generated/ModelElevationReferenceValue;
 	public static final field SEA Lcom/mapbox/maps/extension/compose/style/layers/generated/ModelElevationReferenceValue;
 	public fun <init> (Lcom/mapbox/bindgen/Value;)V
 	public fun <init> (Lcom/mapbox/maps/extension/style/expressions/generated/Expression;)V

extension-compose/src/main/java/com/mapbox/maps/extension/compose/style/layers/generated/LayerProperties.kt

@@ -6534,6 +6534,7 @@ package com.mapbox.maps.extension.style.layers.properties.generated {
     property public String value;
     field public static final com.mapbox.maps.extension.style.layers.properties.generated.ModelElevationReference.Companion Companion;
     field public static final com.mapbox.maps.extension.style.layers.properties.generated.ModelElevationReference GROUND;
+    field public static final com.mapbox.maps.extension.style.layers.properties.generated.ModelElevationReference HD_ROAD_MARKUP;
     field public static final com.mapbox.maps.extension.style.layers.properties.generated.ModelElevationReference SEA;
   }
 

extension-compose/src/main/java/com/mapbox/maps/extension/compose/style/layers/generated/ModelLayerState.kt

@@ -5339,6 +5339,7 @@ public final class com/mapbox/maps/extension/style/layers/properties/generated/L
 public final class com/mapbox/maps/extension/style/layers/properties/generated/ModelElevationReference : com/mapbox/maps/extension/style/layers/properties/generated/LayerProperty {
 	public static final field Companion Lcom/mapbox/maps/extension/style/layers/properties/generated/ModelElevationReference$Companion;
 	public static final field GROUND Lcom/mapbox/maps/extension/style/layers/properties/generated/ModelElevationReference;
+	public static final field HD_ROAD_MARKUP Lcom/mapbox/maps/extension/style/layers/properties/generated/ModelElevationReference;
 	public static final field SEA Lcom/mapbox/maps/extension/style/layers/properties/generated/ModelElevationReference;
 	public fun equals (Ljava/lang/Object;)Z
 	public fun getValue ()Ljava/lang/String;