dds-commander: use std weak pointers instead of raw pointers to temporary hold UI communication channels. It should avoid edge cases when an UI channel is removed for some reason from the list of active channels, but the commander server still in processing of an UI request.
dds-protocol: use Simple Msg command as response to successful or failed commands execution.
dds-protocol: added missing default values and removed unneeded ones.
dds-commander: remove TestChannel and TestConnectionManager classes.