Add explicit support for linking to/from external wheels

[virtuald]

Some of my ideas I trialed in https://github.com/virtuald/hatch-pkgconf-meson leveraging https://github.com/pypackaging-native/pkgconf-pypi... it all comes from stuff originally pioneered in robotpy-build and described in https://discuss.python.org/t/native-dependencies-in-other-wheels-how-i-do-it-but-maybe-we-can-standardize-something/23913

Meson can already link to libraries in other wheels, as long as the wheels are careful about setting up their RPATH correctly. However, I think we would need to detect/massage any .pc files generated by meson to allow the libraries to be correctly linked to from other wheels.

Related meson-python bugs for reading:

• pkgconfig files are installed into "site-packages/.*.mesonpy.libs/pkgconfig" mesonbuild/meson-python#240
• import('pkgconfig').generate() generates wrong Meson introspection data mesonbuild/meson-python#609
• Shared library docs also relevant: DOC: add documentation about using shared libraries mesonbuild/meson-python#700

And discussions that contain comments that are relevant:

• Best practice for optionally bundling a library dependency mesonbuild/meson-python#556
• Properly setting RPATH in Python extensions mesonbuild/meson-python#663

And also this patchelf discussion is useful too:

• Started at binutils 2.43.50: Segmentation fault in test_local_lib mesonbuild/meson-python#698
• Moved to https://bugzilla.redhat.com/show_bug.cgi?id=2321588

And meson bugs too

• intro: add install_rpath to intro-install_plan.json mesonbuild/meson#13625