Error handling on Dashboard should handle some cases more specifically

many errors only appear in "General Messages", but likely should somehow be presented in regular UI. The space where the issue-table is rendered would probably make for a nice place to non-disturbingly and discoverably print such errors because most network errors anyway will lead to no valid table data being displayable. VsCode-like toasters might be another option, not sure whether QtCreator offers something like that.

• e.g. QTCREATORBUG-31781 i.e. unreachable destination
• DNS error: with http://examplenonexisting.com:9090/axivion/  I get "Axivion: NetworkError (http://examplenonexisting.com:9090/axivion/) 3: Host examplenonexisting.com not found" in the logs but no other error
• when the server returns some unexpected content that is just printed to General Messages where I would expect some error like "http://example.com doesn't seem to be a Dashboard Server, got an unexpected response, See General Messages" Also note, that the "Total rows"  counter still says 305