feat(studio): Move Synthetix to a private module

Description

Remove Synthetix and move it to an internal Zapper API module. We need to do some custom things that are not exposed in Studio to remove reliance on subgraphs and enable app interaction indexing.

Checklist

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Zapper-fi / studio

feat(studio): Move Synthetix to a private module #3137

Description

Checklist

How to test?