Add support for DapBreakpointStopped and DapBreakpointConditionStopped signs

[shmerl]

Problem Statement

It would be useful if possible to have separate configurable sings for cases when current position is on the breakpoint. For example DapBreakpointStopped and DapBreakpointConditionStopped.

It would allow to more visually distinguish it from non breakpoint current position. Various visual debuggers do it and can be nice to have.

Thanks!