Improper Shader Subclass handling

[JPMeehan]

Running into a specific shader typing issue while working on the Types project.

1. RenderedSource##createMesh(shaderCls) constructs the mesh with new PointSourceMesh(this.#geometry, shaderCls.create(), state)
2. shaderCls is annotated as typeof AdaptiveLightingShader
3. AdaptiveLightingShader extends AbstractBaseShader extends BaseShaderMixin(PIXI.Shader)
4. PointSourceMesh extends PIXI.Mesh, and the second argument in that constructor is expected to be PIXI.MeshMaterial
5. PIXI.MeshMaterial extends PIXI.Shader, adding properties that are NOT present in the AdaptiveLightingShader inheritance chain.

TL;DR PointSourceMesh canonically expects a different subclass of PIXI.Shader than is provided by Foundry in actual use.

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Separate from #10227 because this seems to be a deeper issue in class construction.

[aaclayton]

bumping to high priority in case this requies API changes. @Feu-Secret to take a quick look. If not we can downgrade it back to the testing phase.