Congress awaits Mueller conclusions as Democrats push for report's release

* Attorney general William Barr to release ‘principal conclusions’* Trump, playing golf near Mar-a-Lago, said to be in ‘good’ mood* Support the Guardian’s journalism. Make a contributionRobert Mueller. Under DoJ rules, the full report does not have to be made public. Photograph: Alex Wong/Getty ImagesWashington and America waited with bated breath on Saturday for the next stage in the Trump-Russia drama: the communication to Congress of the “principal conclusi