First debug log message after connecting to Agent has all-zeros timestamp

[gavanderhoorn]

Minor, but the very first debug listener message received after MotoROS2 connects to the Agent has an all-zeros timestamp associated with it:

[2023-07-14 18:14:40.488481] [192.168.255.1:61992]: THU 1970-01-01 00:00:00.000 Found micro-ROS PC Agent

Everything before and after that is OK.

[gavanderhoorn]

I believe it's due to the conditional used:

motoros2/src/Debug.c

Lines 58 to 72 in f26d997

	if (g_Ros_Communication_AgentIsConnected)
	{
	//get synchronized time from the agent
	int64_t nanosecs = rmw_uros_epoch_nanos();
	Ros_Nanos_To_Time_Msg(nanosecs, &debug_msg_timestamp);
	strftime(timestamp, FORMATTED_TIME_SIZE, "%a %Y-%m-%d %H:%M:%S", localtime_r((const time_t*)&debug_msg_timestamp.sec, &synced_time));
	snprintf(timestamp + strlen(timestamp), FORMATTED_TIME_SIZE - strlen(timestamp), ".%03d ", (int)debug_msg_timestamp.nanosec / 1000000);
	}
	else
	{
	//rmw_uros_epoch_nanos cannot sync with agent because it's not connected
	gettimeofday(&tv, NULL);
	strftime(timestamp, FORMATTED_TIME_SIZE, "%a %Y-%m-%d %H:%M:%S", localtime_r(&tv.tv_sec, &synced_time));
	snprintf(timestamp + strlen(timestamp), FORMATTED_TIME_SIZE - strlen(timestamp), ".%03d ", tv.tv_usec / 1000);
	}

this checks whether the Agent is connected (g_Ros_Communication_AgentIsConnected), but it's likely MotoROS2 hasn't had a chance yet to sync time with the Agent leading to rmw_uros_epoch_nanos() to still return 0.

Perhaps a fallback could be added to use clock_gettime(..) not just when the Agent hasn't connected yet, but also when rmw_uros_epoch_nanos() returns 0?