The "commit_links" table is now called "commit_edges".
There is now a "metrics" table that run measurements have a foreign key
to. This provides canonical metric metadata and will speed up the
initial graph page (before any real data arrives). For now, it will be
overwritten with each new run, but more nuanced config options may be
added later.
Now that HTML is just a Rust value, we can use normal Rust abstractions
for pretty much everything, which is nice. There's still a few parts I'd
like to clean up, but this is already a lot nicer.
