Add more typescript types to module

[cmdcolin]

The module is now compiled with tsc, so incrementally, we can add typescript throughout the codebase for better dev experience for downstream consumers and to catch bugs

[cmdcolin]

fun additional idea: try adding assemblyscript to create wasm. it has syntax very similar to typescript https://www.assemblyscript.org/ (can also use another language that compiles to wasm but assemblyscript seemed interesting)

[cmdcolin]

thanks to @0xorial can mark as closed :)