I'm building a custom destination and want to use Full Refresh Overwrite + Deduped, how do I add it to the spec.json?

I'm sorry, but the provided knowledge sources do not contain specific information on how to add the Full Refresh Overwrite + Deduped sync mode to the spec.json file for a custom destination in Airbyte. However, it's important to note that the Full Refresh Overwrite + Deduped mode is a specific sync mode that Airbyte uses to sync data. In this mode, new syncs will replace all data in the existing destination table and then pull the new data in. The deduped variant also means that the data in the final table will be unique per primary key. This is determined by sorting the data using the cursor field and keeping only the latest de-duplicated data row [source](https://docs.airbyte.com/using-airbyte/core-concepts/sync-modes/full-refresh-overwrite-deduped). For more detailed instructions on how to implement this in your custom destination, I would recommend referring to the Airbyte documentation or reaching out to the Airbyte community for further assistance.