[UserCap BE]: Banner Notifications

Why are we doing this work

In &4315 (closed), we introduced a User Cap setting for self-managed admins to prevent accidental user overages, now we are doing the same for SaaS group owners.

This work will be broken down into the following backend steps:

• Add user cap setting
• Adding/inviting members
• Notifications 👈 we are here
• Member management
• Auto approval
• Approval Modal
• Group access modifications
• Group sharing
• UserCap availability

This issue is to handle the UI banner notifications required for Group owners when a user cap has been reached.

These notifications should only be seen by the root Group owners.

Relevant links

• Epic: &5803 (closed)
• Designs: #321934 (closed)

Implementation plan

• Support the display of a FE banner when the User Cap is reached

Additional notes

There are performance considerations to take into account with the banner. Up until now it has been assumed that the User Cap being reached will be calculated by querying for billable members and comparing to the User Cap value, but we know this is an expensive query that we will wish to reduce the number of calls for.

One potential solution is to add a new soft-lock column for Groups that indicates that the User Cap has been reached, or (possibly more favourable) caching the same in Redis.