Update aggregate counts when adding, updating, copying, or moving nodes

[bjester]

Supersedes: #3733

Summary

Description of the change(s) you made

Adds logic that increments and decrements the total_count, resource_count, and coach_count when adding, updating, copying or moving nodes. The code processes change events, either caused by writes to indexedDB or changes from other users, and uses that information to update the ancestor node counts accordingly

Manual verification steps performed

1. Create a new channel
2. Add a folder Folder A, then a Folder B inside of that, and Folder C inside of B
3. Upload a resource to Folder C
4. Go back to the My Channels page
5. Reopen the channel
6. Observe the resource count on Folder A
7. Duplicate the resource in Folder C
8. Repeat steps 4-6
9. Mark one of the resources in Folder C as coach content
10. Repeat steps 4-6, but verify the coach count shows correctly
11. Delete (move to trash) one of the resources in Folder C
12. Repeat steps 4-6

Does this introduce any tech-debt items?

Deleting a node does not require any of this logic, since we move nodes to the trash tree before deleting them, but it does introduce some inconsistencies.

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References

Fixes #3508
Fixes #2548

Comments

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Contributor's Checklist

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Reviewer's Checklist

This section is for reviewers to fill out.

• Automated test coverage is satisfactory
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[rtibbles]

Changes make sense to me, and the Stream/Dispatcher pattern is very easy to follow and reason about.

Noticed one thing that we should open a follow up issue for, and one other question about a possible edge case, which we may also be able to punt on.

[pcenov]

Hi @bjester - no issues observed while manually testing this one. I did test various scenarios for this one and I can confirm that the resource count when adding, updating, copying or moving nodes is correct.

[bjester]

Woohoo! Great news @pcenov 😅