Deal activity timeline updates

We've updated the deal activity timeline to show many more useful events (including, but not limited to: deal, proposal, change proposal, and invoice creation; document sending; and syncing of invoices to your accounting integrations).

Moving forwards, deal timeline events will also include user attribution, to help you keep track of who has done what.

We received feedback that the activity timeline was slow to load for particularly busy deals, and this change should also improve performance for deals with lots of activity.