Expose RendererPlugin interface as exported typescript types

[eonarheim]

Discussed in https://github.com/excaliburjs/Excalibur/discussions/3233

^{Originally posted by **mccolljr** October 1, 2024} I wanted to play around with a custom renderer plugin, but I'm noticing that the RendererPlugin type isn't exported. TypeScript complains that the type is unexported, and some digging indicates that it is exported from `renderer.d.ts` but not from the `Context` `index.d.ts`. Is this intentional or just an oversight?

[Autsider666]

What would be the requirements for an interface (or type/class) to be exposed (or not) in general?

[eonarheim]

We'll need the interface exported through the graphics index.ts, I think the root index.ts is already exporting all the graphics types.