[EC-635] Extract organizationService.UpdateLicenseAsync to a command (#2408)

* move UpdateLicenseAsync from service to command
* create new SelfHostedOrganizationDetails view model and move license validation logic there
* move occupied seat count logic to database level

src/Infrastructure.Dapper/Repositories/OrganizationUserRepository.cs

@@ -86,6 +86,19 @@ public class OrganizationUserRepository : Repository<OrganizationUser, Guid>, IO
         }
     }
 
+    public async Task<int> GetOccupiedSeatCountByOrganizationIdAsync(Guid organizationId)
+    {
+        using (var connection = new SqlConnection(ConnectionString))
+        {
+            var result = await connection.ExecuteScalarAsync<int>(
+                "[dbo].[OrganizationUser_ReadOccupiedSeatCountByOrganizationId]",
+                new { OrganizationId = organizationId },
+                commandType: CommandType.StoredProcedure);
+
+            return result;
+        }
+    }
+
     public async Task<ICollection<string>> SelectKnownEmailsAsync(Guid organizationId, IEnumerable<string> emails,
         bool onlyRegisteredUsers)
     {