Move TBA team syncing to server

[SUPERCILEX]

Syncing was originally done on the client because cloud functions didn't exist. When functions launched, I didn't consider moving the logic because I thought it would be too expensive. Upon further consideration, it would probably be cheaper to do syncing on the server for a number of reasons:

• We get 5 free GBs of outbound data per month
• The app will no longer be erroneously woken up, thus fixing the broken last used timestamp and allowing for additional account cleanup
• Multiple devices won't step over each other trying to update teams and writing multiple times to the DB
• It's nicer to TBA since we can make a single query and update teams access users

Furthermore, this is better for the client since there won't be wasted bandwidth and app wake-ups.

From an implementation perspective, we query all the teams that haven't been updated in X days and then sync them with TBA. We also add a function that listens to team changes and syncs the team immediately if it's out-of-date.

[SUPERCILEX]

Fixed by 76168ee, 8ceb55e, and c38bc9d.