refactor: move database-related projects to separate folder

SqlData/Application/Cqrs/LectureHall/Queries/GetLectureHallList/GetLectureHallListQueryHandler.cs

@@ -0,0 +1,31 @@
+using MediatR;
+using Microsoft.EntityFrameworkCore;
+using Mirea.Api.DataAccess.Application.Interfaces.DbContexts.Schedule;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Mirea.Api.DataAccess.Application.Cqrs.LectureHall.Queries.GetLectureHallList;
+
+public class GetLectureHallListQueryHandler(ILectureHallDbContext dbContext) : IRequestHandler<GetLectureHallListQuery, LectureHallListVm>
+{
+    public async Task<LectureHallListVm> Handle(GetLectureHallListQuery request, CancellationToken cancellationToken)
+    {
+        var dtos = dbContext.LectureHalls.OrderBy(l => l.Id).Select(l => new LectureHallLookupDto()
+        {
+            Id = l.Id,
+            Name = l.Name,
+            CampusId = l.CampusId
+        });
+
+        if (request is { PageSize: not null, Page: not null })
+            dtos = dtos.Skip(request.Page.Value * request.PageSize.Value).Take(request.PageSize.Value);
+
+        var result = await dtos.ToListAsync(cancellationToken);
+
+        return new LectureHallListVm
+        {
+            LectureHalls = result
+        };
+    }
+}