Add tests and CI workflow

[lordmauve]

Summary

• add pytest-based tests for public interfaces
• add instructions for setting up a venv for tests
• run tests in GitHub Actions on pull requests

Testing

• pytest -q

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https://chatgpt.com/codex/tasks/task_e_6889bb232cec8328a9615f78bd5ab4cf

[Copilot]

Pull Request Overview

This PR adds a comprehensive testing infrastructure with pytest-based unit tests for the pyfxr library's public interfaces and sets up automated testing via GitHub Actions CI.

Key changes include:

• Added unit tests covering core functionality like note conversion, sound generation, and buffer protocol support
• Added documentation for local development setup with virtual environment instructions
• Configured GitHub Actions workflow to run tests automatically on pull requests

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
test_pyfxr.py	Comprehensive test suite covering public API functions and buffer protocol
README.md	Added development setup instructions for testing
.github/workflows/tests.yml	CI workflow configuration for automated testing on PRs

Comments suppressed due to low confidence (3)

.github/workflows/tests.yml:10

• The checkout action version v3 is outdated. Consider updating to actions/checkout@v4 for better performance and security.

      - uses: actions/checkout@v3

.github/workflows/tests.yml:11

• The setup-python action version v4 is outdated. Consider updating to actions/setup-python@v5 for the latest features and security updates.

      - uses: actions/setup-python@v4

.github/workflows/tests.yml:15

• The setup-uv action version v6 may not exist. The latest stable version is typically v3 or v4. Please verify the correct version number.

        uses: astral-sh/setup-uv@v6