fix(rosetta): rosetta extract fails if run after rosetta infuse

[kaizencc]

There is a valid use case to run rosetta extract after rosetta infuse.
However, we run into problems because we fixturize snippets
before we check the cache, and sometimes fixturizing will fail for
infused snippets (specifically, literate sources like integ.blah.lit.ts
will fail).

We do not actually need to successfully fixturize infused examples.
We rely on these examples to be in the cached tablet file and thus
do not need to be compiled and translated again. So we introduce
a new metadata tag, infuse for all infused examples. This tag,
when consumed by extract, will skip any errors associated with
that snippet.

ALSO: increased test timeout from 30000 to 50000 to allow enough
time for mac PR test to succeed.

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[mergify]

Thank you for contributing! ❤️ I will now look into making sure the PR is up-to-date, then proceed to try and merge it!

[mergify]

Merging (with squash)...