Migrating from TestLink to Zephyr Scale - How to Add Attachments Stored on Server?

I'm in the process of migrating from TestLink to Zephyr Scale and have encountered a challenge that I'm hoping to get some advice on. In TestLink, we have extensively used attachments for our test cases, and all these attachments are stored on our server. As we transition to the Zephyr Scale, I want to ensure that we can bring these attachments over without losing any critical data.

Could anyone guide me on how to add attachments to the Zephyr Scale, especially when they are stored on a server? Is there a direct way to upload these attachments in bulk, or will I need to go through a manual process? Any tips on automating this process or tools that could facilitate the migration would be greatly appreciated.

Additionally, if there are any best practices or considerations to keep in mind during this process, I would love to hear about those as well. The goal is to make this transition as smooth as possible, ensuring that all our test cases in the Zephyr Scale have the necessary attachments linked, just like in TestLink.