Implement Engine, add compile_shader to rendering systems

- Implement the initial version of the run method of the glium platform
- Add asset manager to the context of the renderer. I will probably move that to either the engine or somewhere else later.
- Other unimportant stuff that I'm too lazy to include here. Early stage commit messages don't really matter anyways.

raidillon_platform/Cargo.toml

@@ -5,3 +5,4 @@ edition = "2024"
 
 [dependencies]
 winit = "0.30.12"
+raidillon_core = { path = "../raidillon_core" }