gh-155170: Expose extension compiler flags in build details

[pablogsal]

• Issue: Expose extension compiler requirements in build-details.json #155170

[savannahostrowski]

I checked the current build-details.json generation and couldn’t find any existing values under arbitrary_data; this appears to be its first use in CPython. Is the intent to provide a CPython-specific interface now and defer a standardized build-details.json field to a future format version?

If so, could we document the intended semantics and stability of extension_compiler_flags in the docs, including how consumers should expect it to relate to a standardized field later?

It may also be worth clarifying whether entries in this field are required, recommended, or potentially both, since the proposed field does not distinguish between them.

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #34233164 | 📁 Comparing 1de3182 against main (e2118b0)

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2 files changed

± using/configure.html
± whatsnew/changelog.html