feat: added telegram client bot, created DB

JOBot.Backend/Services/gRPC/UserService.cs

@@ -12,15 +12,16 @@ public class UserService(AppDbContext dbContext) : User.UserBase
         RegisterRequest request,
         ServerCallContext context)
     {
-        if(!dbContext.Users.Where(x => x.TelegramId == request.UserId)
-            .Any())
+        if(!dbContext.Users
+               .Any(x => x.TelegramId == request.UserId))
         {
-            dbContext.Users.Add(new Models.User()
+            dbContext.Users.Add(new Models.User
             {
                 TelegramId = request.UserId,
                 Username = !string.IsNullOrEmpty(request.Username) ? request.Username : null
             });
-
+            
+            dbContext.SaveChanges();
             return Task.FromResult(new RegisterResponse
             {
                 Success = true