Implement a mechanism to retrieve/pass-on the commit message for a merge request in Custom Merge Checks

Background

Raised from this question: https://community.atlassian.com/t5/Bitbucket-Cloud-x-Forge-EAP/Introducing-Custom-merge-checks-powered-by-Forge/bc-p/2570223#M10

Currently we struggle with an issue and I don't know how to solve it. We have well defined commit message format in our documentation, and we use Squash merge strategy. The problem is that it's not possible to validate commit message when user merge PR (and developers forget to change the message before merge PR). I was hoping that custom merge checks will allow that, but merge commit message is not available in handler function.

Description

Do you have plans to pass the submitted merge commit message as a Forge input parameter to the `on-merge` trigger, or expose this information via an API?

This would enable users to write checks which can validate the commit message.