stories: sort children of categories (#86168)

We were only sorting the categories, and forgetting to sort the
individual file in each category

---------

Co-authored-by: Dominik Dorfmeister <[email protected]>

Author: JonasBa

static/app/views/stories/storyTree.tsx

@@ -206,6 +206,10 @@ export function useStoryTree(
       root.children = Object.fromEntries(
         Object.entries(root.children).sort(rootCategorySort)
       );
+      // Sort the children of each category by file, folder or alphabetically
+      Object.values(root.children).forEach(child => {
+        child.sort(folderOrSearchScoreFirst);
+      });
     }
 
     // If the user navigates to a story, expand to its location in the tree