Cast node

Cast node - will do codegen in new backend, not worth figuring out right now

hercules_cg/src/cpu_beta.rs

@@ -614,6 +614,7 @@ fn emit_llvm_for_node(
                     todo!()
                 }
             }
+            UnaryOperator::Cast(_) => todo!(),
         },
         Node::Binary { left, right, op } => {
             let opcode = match op {