Improve performance: AOT

[gzurl]

Wasmtime allows AOT (ahead-of-time) compilation.
We might want to enable it and test whether it brings better performance.

If so, we would need to decide whether it's enabled or disabled by default.

[gzurl]

See https://docs.rs/wasmtime/latest/wasmtime/struct.Engine.html#method.precompile_module