Mark init.meta.json as relevant path for directories

src/snapshots/serve_session__just_folder.snap

@@ -1,6 +1,6 @@
 ---
 source: src/serve_session.rs
-expression: tree_value
+expression: "view_tree(&session.tree(), &mut rm)"
 ---
 id: id-1
 name: foo
@@ -12,4 +12,5 @@ metadata:
     Path: /foo
   relevant_paths:
     - /foo
+    - /foo/init.meta.json
 children: []