replace unwraps in parser with error handling

Signed-off-by: squeakbug <[email protected]>

Author: squeakbug

crates/core/src/ast.rs

@@ -111,6 +111,7 @@ pub enum UnlabeledStmt {
     },
     Break,
     Continue,
+    Empty,
 }
 
 #[derive(Debug, Clone)]