Restrict ability to readd a contact to the same sequence

I initially sent this as a bug, but was told it might be a feature, so it may or may not be addressed by the time you start reviewing.

Right now, I can add a contact to the SAME sequence once the sequence completes. This is really not a good idea as they’d be reenrolled in an identical sequence. There is no way to prohibit this from happening.

If the sequence is tied to a Recruiter workflow, you have that safeguard, as you can’t add a duplicate to a job. But if not using recruiter workflow, nothing prohibits it.

I add