Grafana dashboard generator tool

[bendk]

Initial commit for the generate-rust-dashboards tool. This auto-generates Grafana dashboards for teams that own Rust Components. There's still a lot of work to do, but this feels like a good start.

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[bendk]

This tool generates JSON files, which devs can then upload to the Grafana import page. Here's examples from the current config:

• Sync team dashboard.
• DISCO team demo dashboard
• You can click on most of the graphs to get a details page with more info.

There's a bunch of code here and probably lots of opportunities to improve it. I guess the main question is if this is leading us down a path we'll regret in the future. For example are devs going to want to hand-customize their dashboards, which will then be lost if they re-generate and re-import the JSON.

This doesn't handle alerting. AFAICT, that needs to be set up manually.