Reduce AST presence in Bytecode[Interpreter]

e.g., in SpawnData, we currently have (or will shortly have) Spawn* and Proc* elements. The Spawn* is used for TypeInfo lookup inside the interpreter and the Proc* is used for extracting the `config` and `next` functions. If instead we just passed the TypeInfos and the `config` and `next` functions, we could reduce the AST surface exposed inside BytecodeInterpreter.