feat(tvix/eval): add initial barebones compiler

This compiler can only take care of very trivial literals so far.

Change-Id: I9dfac75a801b7235f868061a979ae24159fe1425
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6070
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>

tvix/eval/src/main.rs

@@ -5,6 +5,7 @@ use std::{
 };
 
 mod chunk;
+mod compiler;
 mod errors;
 mod eval;
 mod opcode;