feat(api,app): Community bundles

[PilkeySEK]

Summary

See fluxerapp/fluxer-meta#26
This is a draft PR for community bundles. I am not currently working on this feature, but am opening this draft PR anyway so that others can maybe work on this feature instead (as Lilith said).

What is done already & what still needs to be done:

• Storing bundles in the database
• The following API endpoints:
  • Creating a bundle
  • Accept a bundle (while also being able to select which communities to join)
    • TODO: Delete the bundle when all invites in the bundle have become invalid, or when the bundle expires
  • Viewing an invite bundle (which communities the bundle contains, and how many invites are unavailable due to the invite for that community expiring, being deleted or the invites for that community being disabled)
  • (Admin) List bundles (likely not needed)
  • (Admin) Delete a bundle (likely not needed)
• A UI both in-app and on the web for community bundles, when clicking on their link / navigating to the URL of the bundle
  • The user should be able to select which communities they want to join (or select all)
• A UI for creating bundles (in-app)
  • Selecting which communities (and channels) the invites should be created for
  • User must have permission to create invites in the community
• Verify that the feature can't be exploited for a DoS (invalid requests should be rejected quickly)

The following describes community bundles in their final state, which is not currently achieved:

• What changed: Added "community bundles", allowing users to group multiple invites of different communities into a "bundle", where people who get invited can join all of them or only select ones.
• Why it is correct: /
• Risk: /

Verification

• Tests run:
• Manual checks:
• Screenshots or recordings:

Checklist

• I understand every change in this PR.
• I can explain what it does and why it is correct.
• I disclosed any LLM coding help below.

LLM Disclosure

• None

[PilkeySEK]

Merged the commits from main into this branch, it spammed a bit o_o

[PilkeySEK]

Wait this is wrong, why did that even happen?? Now its just displaying way more changes

[vesaber]

Wait this is wrong, why did that even happen?? Now its just displaying way more changes

i was about to say that
holy shit 😭

[PilkeySEK]

History has been fixed ❤️

[PilkeySEK]

If someone wants to pick this up, would need to fix the tests first (I can't do it right now)

[Kamalaja]

(Admin) List bundles
(Admin) Delete a bundle

I do not think this is needed, as these are just invites with no UGC attached!

[PilkeySEK]

(Admin) List bundles
(Admin) Delete a bundle

I do not think this is needed, as these are just invites with no UGC attached!

Edited it to say "likely not needed"