Auto Assigned Groups feature

[clarkwinkelmann]

Changes proposed in this pull request: Add a new feature that allows auto-assigning (and removing) groups based on custom thresholds.

This feature is sponsored by a Blomstra client.

Reviewers should focus on:

Screenshot

Confirmed

• [x] Frontend changes: tested on a local Flarum installation.

[clarkwinkelmann]

I have added the missing translations, added some tooltips to the buttons and documented the new command in the README (as well as the existing undocumented command)

I have also added some events. I'm not too sure about those. My original idea was to have a single event extend Flarum's GroupsChanged event, but it seems like existing event listeners don't pick up event classes that extend the original. So I triggered 2 different events.

Dispatching only the original group changed event wouldn't be very practical because extensions could not tell where it comes from, and I plan to support logging this into my Audit Log extension. But I think we should still trigger the original Flarum event as well since extensions might be looking at it for other reasons.

[luceos]

@clarkwinkelmann your job AutoAssignUserGroups does not implement Job and is breaking discuss

[clarkwinkelmann]

Oops. It was intentionally not using ShouldQueue and SerializesModel, but I didn't realize there was a missing interface.

Unfortunately I don't have time to look into this until Monday.

[luceos]

Oops. It was intentionally not using ShouldQueue and SerializesModel, but I didn't realize there was a missing interface.

Unfortunately I don't have time to look into this until Monday.

no problem, it's just a job failing in the queue, I have provided a patch as PR but it might have too many interfaces