Addresses https://github.com/coder/nexus/issues/195. Specifically, just
the "tracking templates" requirement:
> ## Tracking in templates
> To enable resource alerts, a user must add the resource_monitoring
block to a template's coder_agent resource. We'd like to track if
customers have any resource monitoring enabled on a per-deployment
basis. Even better, we could identify which templates are using resource
monitoring.
As requested for [this
issue](https://github.com/coder/internal/issues/245) we need to have a
new resource `resources_monitoring` in the agent.
It needs to be parsed from the provisioner and inserted into a new db
table.
