across: Update configs

[pxrl]

Requested by the operator.

📥 Relayer Configuration Added

This PR adds a new configuration file inside the /configs directory for the relayer.

👤 Operator Information

You may provide the following details before submitting your PR. Alternatively, you can reach out to the Across team via private channels.

• Operator Name (optional):
• Description (optional):
• Contact Information (optional):

🧪 Verification Checklist

• I have added my configuration file in the /configs directory.
• I have ensured no other files have been modified.
• I have successfully run the validation script: yarn validate-configs (Optional - this check also runs as a job in CI)