fix: replace for-in loop with forEach in Activity._saveHelpBlocks

 Replaces for-in loop over array with idiomatic forEach for safety and maintainability

Author: AdityaM-IITH

js/activity.js

@@ -1257,11 +1257,9 @@ class Activity {
                 }
             }
 
-            let i = 0;
-            for (const name in blockHelpList) {
-                this.__saveHelpBlock(blockHelpList[name], i * 2000);
-                i += 1;
-            }
+            blockHelpList.forEach((name, i) => {
+                this.__saveHelpBlock(name, i * 2000);
+            });
 
             this.sendAllToTrash(true, true);
         };