add: register and login with DB query AND some struct type correction

internal/api/routes.go

@@ -88,6 +88,11 @@ func SetupRouter(cfg *config.Config, logger *zap.Logger) http.Handler {
 			r.Post("/refresh", authHandler.RefreshToken)
 			r.Post("/logout", authHandler.Logout)
 
+			 // Registration endpoint
+			registerService := service.NewRegisterService()
+			registerHandler := handlers.NewRegisterHandler(logger, registerService)
+			r.Post("/register", registerHandler.Register)
+
 			// ShortLink authentication - no auth required
 			shortLinkHandler := handlers.NewShortLinkHandler(logger, shortLinkService)
 			r.Post("/shortlink", shortLinkHandler.ShortLinkAuth)