[Frontend][Core] Update Outlines Integration from `FSM` to `Guide`

[br3no]

This PR updates the Outlines Integration from FSM to the new Guide interface.

Since I'm not sure where to place the change, I added both labels [Frontend] and [Core].

FIX #3715

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[simon-mo]

I think the test failure in the entrypoints test might be related, and there's merge conflict. 🙏

[br3no]

I'll have a look at the failing frontend test.

[br3no]

I can reproduce the error in the test on my dev environment. The generation does not stop when it should, generating IP addresses like this: 100.101.102.10319216. I'm investigating why this happens and reached out to @rlouf in the outlines discord.

I have pushed some small improvements to the test code:

• ~corrected the regex for IPv4~ the regex was correct. I reverted the change
• changed the pytest fixture to make sure the same python interpreter is used when starting the vLLM server for the integration test (see the warning box here: https://docs.python.org/3/library/subprocess.html#subprocess.Popen)

[navster888]

hey @br3no @simon-mo any updates on getting this PR merged? The pinned version of outlines is preventing us from picking up a bug fix in included in 0.0.40. Is there anyway we can pull the relaxed version constraint into it's own PR to unblock?

[br3no]

I'm having a call with outlines contributors on Thursday. While there is no guarantee we will have a solution for the problem, I'd propose to wait until then. If there's no progress by the end of the week, I'd open a separate PR for the unpinning.

What do you think?

[br3no]

I have opened #4558 because moving to the Guide API will require https://github.com/outlines-dev/outlines/issues/856 to be fixed first.

[br3no]

I have closed #4558 in favor of this PR. I expect to make progress on this next week. Waiting for https://github.com/outlines-dev/outlines/pull/874.

[rlouf]

https://github.com/outlines-dev/outlines/pull/874 merged, thank you for your patience!

[br3no]

Great, thanks for the support @rlouf!

Can you tell already when you plan to release?

[rlouf]

Next week I think. I need to make sure other downstream libraries have pinned the outlines version to avoid surprises.