create hot-reloading example(s)

[RayMarch]

There should be an example crate that shows how to set up hot-reloading.
Maybe even 2 crates

• hot reloading via a separate binary crate that sends the generated pipeline over to a running "engine" process that owns the window.
• hot reloading via something like https://github.com/DioxusLabs/dioxus/tree/main/packages/subsecond