Allow applying a shader to a raster layer.

[Gnative]

Asking to allow us to apply a shader to a specific raster layer. This would open up a lot of possibilities that are not currently possible. This would work how I imagine the Hillshade Layer works and also as shown in mapbox-gl-js

https://github.com/mapbox/mapbox-gl-js/blob/7dec10fe9c1a9a5a7ddf1116dbf03345026245bc/src/shaders/hillshade.fragment.glsl

Examples of use with DEM raster imagery:

• Replicate what Shademap is doing on device - https://shademap.app/@47.0949,15.5751,15z,1719305813809t,0b,0p,0m
• Sea level rise using DEM raster data as shown in this mapbox-gl-js example https://dnomadb.github.io/shader/#6.47/37.527/-122.114
• Indicate different snow heights at different elevations

I imagine there could be quite a few use cases with custom Raster data and Satellite imagery as well