[API] Reconsider API architecture design for events

[kevinydzhu]

Problems with current architecture:

• event data is chaotic - it only happens on branch push. This means that the curve is often discontinuous. Event data should be polled and scanned at regular intervals
• Event types are duplicated - there are plural and singular event types (e.g. new-finding, new-findings). API endpoint shouldn't send duplicate data.
• Events are often not sorted