Allow existing code to be used as library

[patcon]

I wanted it to be more clear how to use this code in a Jupyter Notebook, so I added minimal boilerplate and packaging setup and docs to make that simpler.

(A bunch of places will need the branch and repo updated after approval, but before merge. I'll make suggestions in all those places, but no need to merge them until we're ready, so that others can more easily test)

Here's what's happening:

• reorganized files into proper library locations, added pyproject.toml
• moved example usage into main, so only executed when script called directly (not on library import)
• updated README
• added recommendation of uv for package management
• added version-controlled ipynb with example library usage, and easy deployment on Google Collab. source notebook
• added a stub makefile to make general development tasks simpler
• made sure proper files were ignored for python package that's a library

[patcon]

Suggested change

	pip install git+https://github.com/patcon/polislite.git@python-package
	uv add git+https://github.com/patcon/polislite.git@python-package
	pip install git+https://github.com/eterps/polislite.git@main
	uv add git+https://github.com/eterps/polislite.git@main

[patcon]

Suggested change

	"<a href=\"https://colab.research.google.com/github/patcon/polislite/blob/python-package/polislite_library_usage.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
	"<a href=\"https://colab.research.google.com/github/eterps/polislite/blob/main/polislite_library_usage.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"

[patcon]

Suggested change

	"!pip install git+https://github.com/patcon/polislite.git@python-package"
	"!pip install git+https://github.com/eterps/polislite.git@main"

[patcon]

Suggested change

	"Collecting git+https://github.com/patcon/polislite.git@python-package\n",
	" Cloning https://github.com/patcon/polislite.git (to revision python-package) to /tmp/pip-req-build-b8924s2s\n",
	" Running command git clone --filter=blob:none --quiet https://github.com/patcon/polislite.git /tmp/pip-req-build-b8924s2s\n",
	" Running command git checkout -b python-package --track origin/python-package\n",
	" Switched to a new branch 'python-package'\n",
	" Branch 'python-package' set up to track remote branch 'python-package' from 'origin'.\n",
	" Resolved https://github.com/patcon/polislite.git to commit 9252f24c4acb6ea38a25c1b51b4546d087e91747\n",
	"Collecting git+https://github.com/eterps/polislite.git@main\n",
	" Cloning https://github.com/eterps/polislite.git (to revision main) to /tmp/pip-req-build-b8924s2s\n",
	" Running command git clone --filter=blob:none --quiet https://github.com/eterps/polislite.git /tmp/pip-req-build-b8924s2s\n",
	" Running command git checkout -b main --track origin/main\n",
	" Switched to a new branch 'main'\n",
	" Branch 'main' set up to track remote branch 'main' from 'origin'.\n",
	" Resolved https://github.com/eterps/polislite.git to commit 9252f24c4acb6ea38a25c1b51b4546d087e91747\n",

[eterps]

Hi @patcon, I'll review your proposed changes at a later time as I'm currently down with the flu.

[patcon]

Thanks! Pls do rest up. Eager to work with you on this whenever you find time :)