feat: created register method for entry

JOBot.Backend/Services/gRPC/UserService.cs

@@ -1,19 +1,36 @@
-namespace JOBot.Backend.Services.gRPC;
 
 using Grpc.Core;
 using JOBot.Proto;
+using JOBot.Backend.DAL.Context;
 
-class UserService : User.UserBase
+using Models = JOBot.Backend.DAL.Models;
+
+namespace JOBot.Backend.Services.gRPC;
+class UserService(AppDbContext dbContext) : User.UserBase
 {
+
     public override Task<RegisterResponse> Register(
         RegisterRequest request,
         ServerCallContext context)
-
     {
+        if(!dbContext.Users.Where(x => x.TelegramId == request.UserId)
+            .Any())
+        {
+            dbContext.Users.Add(new Models.User()
+            {
+                TelegramId = request.UserId,
+                Username = !string.IsNullOrEmpty(request.Username) ? request.Username : null
+            });
+
+            return Task.FromResult(new RegisterResponse
+            {
+                Success = true
+            });
+        }
 
         return Task.FromResult(new RegisterResponse
         {
-            UserId = request.UserId
+            Success = false
         });
     }
 }