### Summary
Tracking issue: https://github.com/wormhole-foundation/wormhole-explorer/issues/276
This pull request implements the endpoint `GET /api/v1/top-assets-by-volume`, which returns the assets that have the highest volume. Internally, the endpoint uses data summarized daily to speed up query execution times.
This endpoint has a mandatory query parameter named `timerange`, which must be set to `7d`, `15d` or `30d`.
ftocal
agodnic