Admin controller, Locations controller, requests to add available countries, request to get available countries

SchengenVisaApi/ApplicationLayer/DataAccessingServices/Applicants/NeededServices/IApplicantsRepository.cs

@@ -4,4 +4,8 @@ using Domains.ApplicantDomain;
 namespace ApplicationLayer.DataAccessingServices.Applicants.NeededServices;
 
 /// Repository pattern for <see cref="Applicant"/>
-public interface IApplicantsRepository : IGenericRepository<Applicant>;
+public interface IApplicantsRepository : IGenericRepository<Applicant>
+{
+    /// Find <see cref="Applicant"/> by Identifier
+    Task<Applicant> FindByUserIdAsync(Guid userId, CancellationToken cancellationToken);
+}