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A nice complement to this would be tooling that treats file revisions as time series data, e.g. plot the fire contained percentage over time.

Any existing tools out there?

Not that I've seen. I've written code to do that using the GitPython library in the past, but I had to write it custom for each project - e.g. https://simonwillison.net/2019/Oct/10/pge-outages/