Always require an actor_id to identify the user who caused a specific event in a channel's history.

[rtibbles]

Summary

Description of the change(s) you made

Requires any edits to a channel that changed its soft deletion status or creation of a channel to pass the user_id for the user to whom that change should be attributed.
Consolidates all channel history creation and management onto the Channel model.
Adds and updates tests for the channel history.
Updates every instance in the code base that requires the new actor_id parameter.

This does not ensure history is created by queryset updates, or bulk model creation. Neither are used in our backend for channels, and it would be considerably involved to implement.

Manual verification steps performed

Tests written to ensure behaviour.

Reviewer guidance

How can a reviewer test these changes?

If the tests pass this should be good to go - I've left it as a draft for now in case I missed anything.

See issue below.

References

Fixes #4148

Comments

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Contributor's Checklist

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Reviewer's Checklist

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