[Samuel-Hills]

Summary

Python 3.14 renamed asyncio.events.BaseDefaultEventLoopPolicy to the private _BaseDefaultEventLoopPolicy. trio_asyncio imported only the old public name, so importing the package failed before any event-loop functionality could be used.

This change accepts either name, retaining compatibility with older Python versions while allowing Python 3.14 and later to import normally. It adds an isolated subprocess regression test that imports the package with only the private name exposed, plus the required 160.bugfix.rst release fragment.

Closes #160.

Validation

• Focused compatibility test: 1 passed, 17 deselected
• Python compileall passed.
• git diff --check passed.

The repository-wide flake8 invocation reports many pre-existing baseline violations in unrelated files; no new focused failure was identified.