`rmw_feature_supported` returns `false` for `RMW_FEATURE_MESSAGE_INFO_PUBLICATION_SEQUENCE_NUMBER`

[pszenher]

The rmw_feature_supported function for rmw_zenoh returns false for an argument of RMW_FEATURE_MESSAGE_INFO_PUBLICATION_SEQUENCE_NUMBER, though the implementation ostensibly implements and supports correctly-behaving publication sequence numbers.

rmw_zenoh/rmw_zenoh_cpp/src/rmw_zenoh.cpp

Lines 139 to 150 in 4dcd184

	bool rmw_feature_supported(rmw_feature_t feature)
	{
	switch (feature) {
	case RMW_FEATURE_MESSAGE_INFO_PUBLICATION_SEQUENCE_NUMBER:
	return false;
	case RMW_FEATURE_MESSAGE_INFO_RECEPTION_SEQUENCE_NUMBER:
	return false;
	case RMW_MIDDLEWARE_SUPPORTS_TYPE_DISCOVERY:
	return true;
	case RMW_MIDDLEWARE_CAN_TAKE_DYNAMIC_MESSAGE:
	return false;
	}

Is this an artifact left from prior to the implementation of publication sequence numbers in rmw_zenoh, or is there an issue with the current implementation that suggests that the publication_sequence_number field of returned rmw_message_info_t messages shouldn't be relied on?

Note that the rmw_feature_supported function does not appear to have wide use among client library implementations currenly, with rcl using it only for a single check of RMW_MIDDLEWARE_SUPPORTS_TYPE_DISCOVERY, and neither rclcpp nor rclpy referencing it at all.

[JEnoch]

I think it's an oversight.
The rmw_feature_supported() function was implemented in Sept 2023, while the the publication sequence number was implemented in March 2024.

Would you like to contribute with a fix ?