Add geospatial Kotlin sample for ARCore Android SDK

[Kingjha13]

This PR adds a Kotlin version of the Geospatial sample for the ARCore Android SDK.

Currently, the repository includes geospatial_java but does not provide a Kotlin equivalent sample. This contribution adds geospatial_kotlin with the same core functionality adapted using the Kotlin sample structure used in other ARCore examples.

Included:

Geospatial API support in Kotlin
VPS availability checks
Geospatial / Terrain / Rooftop anchors
Streetscape geometry rendering
Required assets, resources, and permissions
Updated Gradle + manifest configuration

Tested successfully on a physical ARCore-supported Android device.

This improves consistency across samples and helps developers who prefer Kotlin for Android development.

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