新增：用户项目时间筛选项

app/services/api/v1/users/projects/list_service.rb

@@ -18,8 +18,8 @@ class Api::V1::Users::Projects::ListService < ApplicationService
     @sort_by = params[:sort_by] || 'updated_on'
     @sort_direction = params[:sort_direction] || 'desc'
     @search = params[:search]
-    @start_at = params[:start_at]
-    @end_at = params[:end_at]
+    @start_at = params[:start_at].to_i
+    @end_at = params[:end_at].to_i
     @current_user = current_user
   end