Set default parameters and fix bound ordering in Python index_search

[jdaymude]

Fixes #113 and resolves #114. Specifically, the Python version of index_search now:

• Respects the order of bound strings provided as its bound_strs parameter.
• Sets default parameter values equivalent to what is considered default in the CLI and in the index function, which can be overridden as needed.

The documentation and Python tests are updated accordingly.

[jdaymude]

Our GitHub CI is somehow not seeing the changes I made to python.rs when rebuilding the Python package, so it's failing its (new) pytest which expects the bound strings to be a list instead of a set and allows default parameter values in index_search. I have no idea why; I can pass all Python tests locally. @AgentElement, can you look at this when you get a chance?

UPDATE 1: According to the pip documentation,

pip looks for packages in a number of places: on PyPI (or the index given as --index-url, if not disabled via --no-index), in the local filesystem, and in any additional repositories specified via --find-links or --extra-index-url. There is no priority in the locations that are searched. Rather they are all checked, and the “best” match for the requirements (in terms of version number - see the specification for details) is selected.

Is it possible that somewhere amidst our new v0.5.0 release, our runner is pulling from PyPI instead of the local repository specified by --find-links dist in our actions spec?

UPDATE 2: Yup, this was the problem. I have added --no-index to the pip installation command for our own package so that it never confuses the live version on PyPI with the locally built version that should be tested.