Browser Extension Telemetry documentation

Created by: muratsu

We are currently not documenting the data we're collecting.

There are two types of data we're collecting and want to document.

1. Individual actions These are the individual actions that can be tracked via amplitude and is useful for building user stories etc. I don't think we need too much detail but it would be have a source of truth for understanding what event does what without looking at the code.

2. Collective data (pings data) These are aggregate data collections that are sent from self-hosted instances. A good example for this type of documentation is the code insights pings page