attachEndpointsToAllowedPathsOnly

Each of the route's endpoints joins the path network at its closest vertex on its level. When true, a vertex is skipped if every path leaving it, for the start, or entering it, for a destination, has a flag in avoidFlags. Paths that run both ways count as both. When false, the closest vertex is always used, which usually makes the route RouteResult.Failure.Unreachable if all its paths are avoided. If no vertex qualifies, the route is RouteResult.Failure.OriginNotOnPaths or RouteResult.Failure.DestinationsNotOnPaths.