chore: set typing for from_code_optional to use Self (#761)

Author: Lash-L

roborock/data/code_mappings.py

@@ -77,7 +77,8 @@ def from_code(cls, code: int) -> Self:
         raise ValueError(message)
 
     @classmethod
-    def from_code_optional(cls, code: int) -> RoborockModeEnum | None:
+    def from_code_optional(cls, code: int) -> Self | None:
+        """Gracefully return None if the code does not exist."""
         try:
             return cls.from_code(code)
         except ValueError:

roborock/protocols/b01_q10_protocol.py

@@ -45,8 +45,7 @@ def _convert_datapoints(datapoints: dict[str, Any], message: RoborockMessage) ->
         except ValueError as e:
             raise ValueError(f"dps key is not a valid integer: {e} for {message.payload!r}") from e
         if (dps := B01_Q10_DP.from_code_optional(code)) is not None:
-            # Update from_code to use `Self` on newer python version to remove this type ignore
-            result[dps] = value  # type: ignore[index]
+            result[dps] = value
     return result