Refactor User Response Handling in API Endpoints

- Updated user-related API handlers to return user entities directly instead of using the ToResponse method, simplifying response structures.
- Modified service methods to return UserResponse types instead of User, enhancing consistency in response formats.
- Improved pagination handling in the response package by setting default values for sorting parameters, ensuring more predictable behavior in API responses.

pkg/response/response.go

@@ -191,11 +191,21 @@ func NewPagination(c echo.Context) *Pagination {
 		offset = 0
 	}
 
+	sortBy := c.QueryParam("sort_by")
+	if sortBy == "" {
+		sortBy = "created_at"
+	}
+
+	sortOrder := c.QueryParam("sort_order")
+	if sortOrder == "" {
+		sortOrder = "desc"
+	}
+
 	return &Pagination{
 		Limit:     limit,
 		Offset:    offset,
-		SortBy:    c.QueryParam("sort_by"),
-		SortOrder: c.QueryParam("sort_order"),
+		SortBy:    sortBy,
+		SortOrder: sortOrder,
 	}
 }