feat: add Linux aarch64 wheel builds via ubuntu-24.04-arm runner

[KE7]

Summary

Linux aarch64 (ARM64) wheels are not currently available on PyPI for python-fcl, making it uninstallable on platforms such as NVIDIA Jetson, DGX Spark, AWS Graviton, and other aarch64 servers. This PR adds native Linux ARM64 wheel builds.

Approach

Follows the same pattern used to add macOS ARM support in #74: add a native ARM runner to the platform matrix rather than using QEMU emulation.

• Add ubuntu-24.04-arm to the platform matrix in push.yml and release.yml
• Remove the explicit archs = ["x86_64"] restriction from pyproject.toml so cibuildwheel auto-detects the native arch per runner (x86_64 on ubuntu-latest, aarch64 on ubuntu-24.04-arm)
• No changes to build_dependencies/install_linux.sh — it builds all C++ deps (eigen, libccd, octomap, fcl) from source via cmake, which is architecture-agnostic

Testing

All 15 tests pass on linux/aarch64 (verified locally on a native ARM64 machine):

platform linux -- Python 3.11.14, pytest-9.0.2
collected 15 items

tests/test_fcl.py::TestFCL::test_managed_collisions PASSED
tests/test_fcl.py::TestFCL::test_managed_distances PASSED
tests/test_fcl.py::TestFCL::test_many_objects PASSED
tests/test_fcl.py::TestFCL::test_nearest_points PASSED
tests/test_fcl.py::TestFCL::test_pairwise_collisions PASSED
tests/test_fcl.py::TestFCL::test_pairwise_continuous_collisions PASSED
tests/test_fcl.py::TestFCL::test_pairwise_distances PASSED
tests/test_fcl.py::TestFCL::test_updates PASSED
tests/test_precision.py::TestPrecision::test_mgr_mgr_coll PASSED
tests/test_precision.py::TestPrecision::test_mgr_mgr_signed_distance PASSED
tests/test_precision.py::TestPrecision::test_mgr_obj_coll PASSED
tests/test_precision.py::TestPrecision::test_mgr_obj_signed_distance PASSED
tests/test_precision.py::TestPrecision::test_obj_obj_coll PASSED
tests/test_precision.py::TestPrecision::test_obj_obj_signed_distance PASSED
tests/test_precision.py::TestPrecision::test_obj_obj_simple_distance PASSED

15 passed in 0.08s