migrate 392 questions to pattern format

backend/data/questions/binary-tree-right-side-view.yaml

@@ -6,9 +6,12 @@ leetcode_url: https://leetcode.com/problems/binary-tree-right-side-view/
 categories:
   - trees
 patterns:
-  - bfs
-  - dfs
-  - tree-traversal
+  - slug: bfs
+    is_optimal: true
+  - slug: dfs
+    is_optimal: false
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def right_side_view(root: TreeNode) -> list[int]:"