This is the top level improvement ticket for engine work to support customer facing metrics.

The required engine work in Q2 is exposing the below, likely in the stats command:

• Tracking how far behind a change stream source processor is from the current oplog entry (we might need to do the same for kafka)
• Watermark
• End to End Processor Latency
• Worker level-- CPU Use (this might be better implemented outside of the engine, we can consider using FTDC for it if we want to use the engine)

See the priority metrics in this spreadsheet: https://docs.google.com/spreadsheets/d/1xMkpOokwbV7dcmsfsIpWUbcY2N9NIQU9lk02itb_ij0/edit#gid=0... And this table in the product description: https://docs.google.com/document/d/1AkCzgbd3z0gyWgLp46ptubV44zC-naUpi-_poHxKCyE/edit