migrate 392 questions to pattern format

backend/data/questions/word-break.yaml

@@ -8,7 +8,8 @@ categories:
   - strings
   - hash-tables
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def word_break(s: str, word_dict: list[str]) -> bool:"