fix: wrap okCode in else to prevent execution after error path

Success-exclusive code was emitted outside the if-else, so it ran even
when the call failed. Now it's wrapped in else { ... } — shared code
(blocks reachable from both error and success paths) stays outside.

codegen/index.js

@@ -161,8 +161,9 @@
       Array.from(shared), new Set(), visited, isDecision, loopTargets
     );
 
-    var out = ifHeader + " {\n" + errCode + "}\n";
-    if (okCode) out += okCode;
+    var out = ifHeader + " {\n" + errCode + "}";
+    if (okCode) out += " else {\n" + okCode + "}";
+    out += "\n";
     if (sharedCode) out += sharedCode;
     return out;
   };