only_straight_on restriction is not supported

Hello,

`only_straight_on` restriction is not supported. Please check following route:

https://maps.openrouteservice.org/directions?n1=50.157696&n2=25.30745&n3=17&a=50.157645,25.305556,50.157398,25.308088&b=0&c=0&k1=en-US&k2=km


Thanks
Dima

Start by reproducing the linked route in the openrouteservice directions API and inspect the issue discussion for details about the `only_straight_on` restriction. Trace how turn restrictions are processed, then verify that the reported route honors this restriction and add or run coverage for the case.

Written by the indexing model from the issue text.