Is there a way to configure Sonar to ignore single-line if-statements like
if (value == true) return;
while marking multi-line if-statements witout braces such as
if (value == true)
return;
as violations?
There is no rule that matches your needs but you can write your own rule with XPath. You can find a tutorial here
If you don't know how to extend the coding rules of sonar you can find a tutorial here