fix: worker not being called to work on sorting

src/routes/xp/programs/my_computer/sort.js

@@ -51,7 +51,7 @@ onmessage = async ({data}) => {
             return elm[option_key];
         }
     }
-    
+
     let sorted_items = sort(items).by([predicate]);
 
     postMessage({id, sorted_items, type: 'sorted'})

src/routes/xp/programs/my_computer/viewer.svelte

@@ -53,6 +53,8 @@
                 last_sort_tx_hash = hash;
                 worker.postMessage({type: 'sort', hash, ...hash_object});
             }
+        } else {
+            last_sort_tx_hash = null;
         }
     }