RE: https://github.com/coder/coder/issues/15740,
https://github.com/coder/coder/issues/15297
In order to add a graph to the coder frontend to show user status over
time as an indicator of license usage, this PR adds the following:
* a new `api.insightsUserStatusCountsOverTime` endpoint to the API
* which calls a new `GetUserStatusCountsOverTime` query from postgres
* which relies on two new tables `user_status_changes` and
`user_deleted`
* which are populated by a new trigger and function that tracks updates
to the users table
The chart itself will be added in a subsequent PR
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Co-authored-by: Mathias Fredriksson <mafredri@gmail.com>
