Resolve deprecation warnings when building Cython examples

[oleksandr-pavlyk]

This PR adds conda list of the build environment to help understand the origin of compiler warnings in CI which are not reproducible locally.

Edit:

This PR resolves the issue by upgrading building system for Cython examples to use scikit-build.
CMake ensures that header files from the correct location are used.

---

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[github-actions]

Deleted rendered PR docs from intelpython.github.com/dpctl, latest should be updated shortly. 🤞

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_325 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[coveralls]

coverage: 87.659%. remained the same
when pulling ac978f1 on triage-example-warnings
into 5352dd5 on master.

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_326 ran successfully.
Passed: 895
Failed: 1
Skipped: 118

[oleksandr-pavlyk]

The warnings in test_examples_linux step come from

In file included from blackscholes/blackscholes.cpp:1325:
In file included from /usr/share/miniconda/envs/examples/include/python3.11/../sycl/sycl.hpp:25:
In file included from /usr/share/miniconda/envs/examples/include/python3.11/../sycl/detail/core.hpp:21:
In file included from /usr/share/miniconda/envs/examples/include/python3.11/../sycl/accessor.hpp:11:

The folder $CONDA_PREFIX/include/python.311/../sycl does not exist for me locally, since my DPC++ comes from system-wide installation.

[oleksandr-pavlyk]

The immediate reason is that intel-sycl-rt package seems to include SYCL headers:

$ grep -r "sycl.hpp" $CONDA_PREFIX/conda-meta/
/localdisk/work/opavlyk/mamba/envs/test_examples/conda-meta/intel-sycl-rt-2025.0.4-intel_1519.json:    "include/sycl/CL/sycl.hpp",

Compiler finds these header files instead of those packages in the compiler itself in build_env environment.

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_345 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_346 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_340 ran successfully.
Passed: 893
Failed: 3
Skipped: 118

[oleksandr-pavlyk]

I've changed build system for Cython examples over to scikit-build, and the warnings are now all gone.

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_341 ran successfully.
Passed: 895
Failed: 1
Skipped: 118

[ndgrigorian]

Warnings are gone so this LGTM!