Add RandomDirectoryContext manager and API docs

[bittner]

Adds a new context manager to allow verifying the code's independence of the CLI execution location.

Enhances the documentation by adding an API documentation chapter, auto-generated from source code.

[Copilot]

Pull request overview

This PR adds a new RandomDirectoryContext context manager to help test CLI programs' independence from their execution directory, and introduces auto-generated API documentation using Sphinx's autodoc extension.

• Adds RandomDirectoryContext class that temporarily changes to a random temporary directory during test execution
• Sets up Sphinx autodoc for automatic API documentation generation from source code docstrings
• Updates tutorial documentation to include usage examples for the new context manager

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
cli_test_helpers/decorators.py	Implements RandomDirectoryContext class inheriting from TemporaryDirectory with directory switching logic and enhanced docstrings for ArgvContext
cli_test_helpers/init.py	Exports the new RandomDirectoryContext class in the package's public API
tests/test_decorators.py	Adds test case test_random_directory_context() to verify directory switching and restoration behavior
pyproject.toml	Adds PTH109 to ruff ignore list (allows os.getcwd() usage instead of requiring Path.cwd())
docs/conf.py	Configures Sphinx to import the package and enables autodoc extension for API documentation
docs/index.rst	Adds API documentation page to the documentation table of contents
docs/api.rst	Creates new API documentation page with autoclass/autofunction directives for all public APIs
docs/tutorial.rst	Updates references to use Sphinx cross-references and adds tutorial section for RandomDirectoryContext

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[bittner]

@copilot The tests fail on macOS only. See job 57723418134 for an example:

>           assert new_dir == random_dir, "Does't behave like TemporaryDirectory"
E           AssertionError: Does't behave like TemporaryDirectory
E           assert '/private/var...T/tmpp6s4ranh' == '/var/folders...T/tmpp6s4ranh'
E             
E             - /var/folders/_l/91ns3hs96sd11p4_lzxh1l140000gn/T/tmpp6s4ranh
E             + /private/var/folders/_l/91ns3hs96sd11p4_lzxh1l140000gn/T/tmpp6s4ranh
E             ? ++++++++

os.getcwd() appears to yield the same path but prefixed with /private/.

• Why does the TemporaryDirectory context manager yield a different directory than os.getcwd()?
• Is the infrastructure setup on the macOS runners know to be particular? (Is "private" a mount point or a symbolic link?)
• Is there a better, more robust choice instead of TemporaryDirectory as a base class?

[Copilot]

@bittner I've opened a new pull request, #69, to work on those changes. Once the pull request is ready, I'll request review from you.