wasm: Refactor fully to use symbolic indices

[Derppening]

Refactor all usages of numeric indices to symbolic indices, so that all top-level module constructs are named.

No functionality changes, except all functions are exposed as element segments. This allows any function to be called using call_ref for consistency.

[LPTK]

Neat, thanks!

But is there any plan to move away from the deprecated stuff? Did you leave it there to help the FYP students? Also, does it really need to be deprecated?

[Derppening]

Neat, thanks!

But is there any plan to move away from the deprecated stuff?

The implementation has fully moved away from the deprecated stuff. The only locations that still retains numeric indices is getType and getFunc for (temporary) backwards compatibility.

Did you leave it there to help the FYP students?

Yes. I have tried to make all changes API-compatible to ensure that their changes can be applied on top of this with minimal changes.

Also, does it really need to be deprecated?

I am not sure. It just seems like a good idea to force people to move away from using numeric indices before it is fully removed or made private within the Ctx implementation.