Separate engine's runtime and user's scene in wasm

[AzurIce]

So that, we can re-use ranim's wasm file in web instead of linking all scenes with engine into the same wasm file.

[AzurIce]

Each wasm module has its own linear memory space, that makes the interop between two wasm module a pain.

Structs like Scene or SealedRanimScene contains pointers in it, that makes simply copying it across the modules won't work.

A wasm module is more like already a "dylib", and it can only be load by the browser with isolated memory address?

Maybe wasm 3.0 has something can make it across?

Help wanted.

[AzurIce]

Maybe related: https://github.com/WebAssembly/component-model