fix dependency issues - domain service

[StefanSchade]

adapters depend on domain

-to prevent use of the aggregates in the adapters, define dtos in ports

navigation service needs repos

• is it legitimate for domain services to do what the location service does
• use a query abstachtion?

the application layer is known to the adapter(s)

• create abstractions in port layer to access them

[StefanSchade]

We start with the biggest issue: the domain_service was relocated to the application layer before. For it to reside in the domain layer it has to be independent of the port layer and therefore of the repositories. We therefore introduce thee new concept of "domain queries". These reside in the domain and are implmeneted by the port layer. Access to the interface is therefore allowed for a domain service.

[StefanSchade]

commit 10948cb906eef7d6dbfae71e3d46ca8ec96879dd

creates a domain query object and starts to implement it

[StefanSchade]

commit d53c153a612e94e20efb508122cb59b1ebea5f42

by now the domain query "passage query" was implemented and connected, but now I rename it into location query since it seems advisable to group these queries by aggregate. cross-aggregate logic schould be in domain services not in queries... I think - lets see how this works