feat: clean up the machine a bit

crates/uplc/src/machine/error.rs

@@ -0,0 +1,9 @@
+use thiserror::Error;
+
+use super::ExBudget;
+
+#[derive(Error, Debug)]
+pub enum Error {
+    #[error("Over budget mem: {} & cpu: {}", .0.mem, .0.cpu)]
+    OutOfExError(ExBudget),
+}