Updated type hint of the handler in the register_state function

src/bot/helper_functions.py

@@ -18,7 +18,7 @@ states: dict[tuple[int, int], Handler] = {}
 
 def register_state(
     message: Message,
-    handler: Callable[[Message], Any],
+    handler: Handler,
 ) -> None:
     states[(message.chat.id, message.from_user.id)] = handler