There have been many threads over the years with this or a similar question and I think it's safe to say the answer is "no". Just search the "community" for Bose. Unless you can connect the soundbar to the TV via HDMI-ARC and use CEC (or Bravia-sync, I think Sony calls it) there's no way to configure a Roku remote to control anything other than a TV.
Roku Community Streaming Expert
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