Building DevTools is currently the long pole for the runtime CI job.
Let's see if we can get the overall runtime for runtime build and test
down by speeding this one step up.
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* #32267
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…un_devtools_e2e_tests (#32267)

I just noticed that we don't actually need to let the devtools build
finish first because the e2e tests don't use those built files. We can
decouple them to allow them to run in paralllel.

…eyCommit Phase (#32254)

When a named ViewTransition component unmounts in one place and mounts
in a different place we need to match these up so we know a pair has
been created. Since the unmounts are tracked in the snapshot phase we
need some way to track the mounts before that.

Originally the way I did that is by reusing the render phase since there
was no other phase in the commit before that. However, that's not quite
correct. Just because something is visited in render doesn't mean it'll
commit. E.g. if that tree ends up suspending or erroring. Which would
lead to a false positive on match. The unmount shouldn't animate in that
case.

(Un)fortunately we have already added a traversal before the snapshot
phase for tracking suspensey CSS. The `accumulateSuspenseyCommit` phase.
This needs to find new mounts of Suspensey CSS or if there was a
reappearing Offscreen boundary it needs to find any Suspensey CSS
already inside that tree. This is exactly the same traversal we need to
find newly appearing View Transition components. So we can just reuse
that.