ua-parser-rs: add build-ua-parser-rs.yml for riscv64 wheels

[luhenry]

• Package: ua-parser-rs
• Version: 0.1.5
• Source: https://github.com/ua-parser/uap-python/tree/main/ua-parser-rs
• Docs: https://github.com/ua-parser/uap-python

Builds the pyo3/maturin native accelerator for ua-parser's regex resolver. Upstream publishes no riscv64 wheel.

Mirrors the py-release-wheels/py-release-tests jobs of upstream's release-wheels.yml.

Differs from upstream

• Uses cibuildwheel instead of raw maturin-action - repo convention, same build inputs.

Testing

• Smoke-tests the compiled extension directly, then installs the top-level ua_parser package from the same checkout and runs tests/test_core.py -k regex, the upstream conformance suite for this backend, against the real uap-core UA test data.

License: OK

Built on cp310; wheel is abi3 and reused for cp311-cp314. cp314t builds separately (pyo3 disables abi3 under free-threading).