### What?
This PR ensures the jest configuration is json-serializable. It also
adds a bunch of typescript types.
### Why?
Jest requires that the configuration be json-serializable. See #47407
for details on the issues caused when it isn't. However, prior to this
commit, we were passing the entire next config as a property in the swc
jest transformer options. The next config includes some fields that are
not serializable, such as some functions.
### How?
In this PR we instead pluck the fields out of the next config that we
actually need and pass only those into the swc transformer.
This PR also adds a bunch of more precise typescript types where we were
previously just using `any`. This helps confirm that the configs are
being threaded through correctly. I think this type safety is enough to
confirm this commit and adding tests would just be redundant.
Closes NEXT-901
Fixes#47407
fix NEXT-901 ([link](https://linear.app/vercel/issue/NEXT-901))
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Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
Co-authored-by: Jiachi Liu <inbox@huozhi.im>
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