create new "Failed" state

it is very common that integrations of particular changes fail because of entirely unrelated changes.
this is quite an annoyance because of the subsequent clicking necessary to re-stage the good changes. topic reviews have been suggested as a possible solution, but this concept is flawed. some even see the problem as a disincentive to make their changes atomic.
also, most people care only for their own changes, so integrations are unnecessarily delayed.

therefore i suggest the introduction of a new state Failed which is automatically entered by all changes which failed integration. per project+branch there would be a filter to show all such changes, and a button to re-stage them en masse. of course, each change would have an individual button to transition it to Review in Progress state, to exclude the actually offending changes..

in a next step, the overview of failed changes chould be annotated by automated offender identification (based on correlating error messages with paths touched by commits) to ease QA's work. see also QTQAINFRA-869.