fix: match destinationSettler to counterpart

[rymcol]

Description

Enforces destinationSettler == counterpart

Motivation and Context

Prevents edge cases where a user could specify an incorrect settler

How Has This Been Tested?

manually

Types of changes (remove all unchecked types)

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Style (style only changes)
• Docs
• Refactor (code that does not add new functionality nor fixes a bug)

Checklist:

• If my change requires a change to the documentation, I have updated the documentation accordingly, and in either case, have checked this box to attest to my assessment of this requirement with regard to my change.
• If my change requires additions or updates to any deployment scripts to ensure that the protocol is functional (Makefile, Dockerfile, Forge Script, etc.), I have made these changes, and in either case, have checked this box to attest to my assessment of this requirement with regard to my change.
• If my change requires additional test coverage, I have created those tests accordingly, and in either case, have checked this box to attest to my assessment of this requirement with regard to my change.

[evchip]

please run forge fmt to lint

[evchip]

this comment seems superfluous