New feature request: MultiXactId reporting

[psvampa]

Hello Jobin,
Currently, pg_gather reports the database/relation age. Over the last time, I faced a few MultiXactId scenarios. I would like pg_gather to report this if possible.
Best Regards,

[jobinau]

Thank you, @psvampa, for raising this new feature request.
This is something which I have been considering for quite long. It wasn't included because there was little clarity on what could add value. Let me think further about this.
Meanwhile, I welcome ideas about how to have a meaningful/effective analysis.

[psvampa]

#42 adds DB-level multixactid verification.
If it becomes helpful, a threshold-based warning could be added, similar to the report's other warnings.