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Description

I had been using theproject setting for quite awhile, unaware that there's a newprojectService setting that's generally recommended in its place. I wonder if there could be some warning to help users discover this - either printed at runtime or via compile time type checking.

The docs say:

We now recommend usingprojectService instead of project for easier configuration and faster linting.

My own experience withprojectService has been that it is indeed faster. I understand from#8031 that it's not the case for 100% of projects. However, when there is a difference, it looks to be on the order of a few percent. On the other hand, theproject setting has much more ability for users to create pathological settings that can really harm their performance in a very meaningful way (e.g.#2611)

I also see in#8031 that it says:

Our priority for the next year will be to improve the new Project Service API so that it works in all places the traditional Program API does.
We won't remove the traditional project program behavior unless and until the new Project Service API is able to fully replace it.

I'm not sure if there's a list of differences that exists currently. It may be hard to discover the ways in which differences remain. Deprecating theproject setting would encourage users to attempt a migration and report any difficulties.

Additional Info

If there is some decision to help more actively push users towardsprojectService it may be worth clarifying the updated stance in the pending blog post (#8031) and docs. I think in either case, theproject setting would continue to be supported for awhile. It's really just a question of whether users should more actively be made aware ofprojectService as an alternative