build: add wheels to pypi

[govinda-kamath]

Closes #427.

• Adds a build-wheels job to CI that uses cibuildwheel to build binary wheels for:
  • manylinux and musllinux — x86_64 and aarch64 (native arm64 runner)
  • macos — arm64 and x86_64
  • Python 3.9–3.14 (also adds 3.14 to the existing build-and-test matrix)
• Adds a publish job that runs automatically on v* tags, after both build-and-test and build-wheels pass. It publishes the sdist and all wheels to PyPI using OIDC trusted publishing (no API token needed).
• PR development was AI assisted.

Before the first tagged release, one manual step is required on PyPI - add a Trusted Publisher for this repo.

[govinda-kamath]

Looks like the wheels build successfully on my fork [GHA]; but I seem to see a test failing -- dont think it should be due to this change though.

=================================== FAILURES ===================================
________________________________ test_issue_118 ________________________________

    def test_issue_118():
        p = psutil.Process(os.getpid())
        start_fds = p.num_fds()
        a = pybedtools.example_bedtool("a.bed")
        b = pybedtools.example_bedtool("b.bed")
        for i in range(100):
            c = a.intersect(b)
            c.field_count()
        stop_fds = p.num_fds()
>       assert start_fds == stop_fds
E       assert 44 == 42

pybedtools/test/test_issues.py:71: AssertionError
=========================== short test summary info ============================
FAILED pybedtools/test/test_issues.py::test_issue_118 - assert 44 == 42
================== 1 failed, 554 passed, 3 xfailed in 39.02s ===================