SCM Skip: Pattern .*\[ci-skip\].* NOT matched on message: Add AdoptionService and TrialStayService
Introduce AdoptionService and TrialStayService providing CRUD operations, basic validations and logging for adoption and trial-stay flows. AdoptionService enforces non-null inputs, pet availability, adoption date presence, status update on update, and prevents deletion unless adoption status is FINISHED. TrialStayService enforces date and adoption presence on create, supports full updates, and prevents deletion when an adoption is associated. Also include minor whitespace/formatting cleanup in TrialStayEntity.