Support Unichain Bridging Routes

Summary

Author: Unichain Status : Proposed Related Discussions: https://forum.across.to/t/support-unichain-bridging-routes/2012 ------------------------------------------------------- ### Summary: The Unichain core team proposes the integration of Across to Unichain. In collaboration with the Across core team, the Unichain team has been working to ensure the new chain requirement and technical feasibility (more below in the...