I would like to learn about the leading shipping rate management tools that help businesses calculate, compare, and optimize shipping costs across multiple carriers and delivery options. Which platforms—such as ShipStation, EasyShip, Shippo, Ordoro, ShippingEasy, MetaPack, Stamps.com, ShippyPro, Pitney Bowes SendPro, and Convey—are widely used for automating shipping workflows, comparing real-time carrier rates, generating labels, and tracking deliveries, and how do they compare in terms of features like multi-carrier rate comparison, automation rules, e-commerce platform integrations, analytics dashboards, international shipping support, scalability, and ease of deployment for e-commerce companies, logistics providers, and enterprises managing complex shipping operations?