Update the documentation following the PyPI changes

[joasode]

The major edits in the PR is related to #102 , as seen in the following sections:
https://cotainr--127.org.readthedocs.build/en/127/development/test_suite_ci_cd.html#the-test-suite
https://cotainr--127.org.readthedocs.build/en/127/development/test_suite_ci_cd.html#continuous-deployment
https://cotainr--127.org.readthedocs.build/en/127/development/releasing.html#release-process
https://cotainr--127.org.readthedocs.build/en/127/getting_started.html
The corresponding README is in #120 as it is not in the documentation
closes #102

[Chroxvi]

Here are some suggestions for taking a slightly different approach to this docs update, by:

• Syncing the docs to the state of the main branch following the merge of #117, #118, #120, #126.
• Describing dependency installation a little more generic, only recommending the use of uv.
• Restructuring things to be more in line with the rest of the documentation - though this may need an even larger overhaul soon.

Furthermore, I think these other parts of the docs need an update as part of this PR:

• The Schedules tests section needs a minor update to reflect our new uv based setup.
• The Docs dependencies section needs an update about installing the "docs" dependency group from the pyproject.toml file - similar to how the "test" dependency installation is described in this PR.
• The pre-commit section needs an update about installing the "lint" dependency group from the pyproject.toml file - similar to how the "test" dependency installation is described in this PR.
• I think the CLI internals section should just assume you have installed cotainr via pip and, thus, only mention running cotainr build ... etc. Maybe it should still mention the bin/cotainr script as an alternative to the pip installed entrypoint.

[Chroxvi]

Look good to me. I noted two typos, you might want to correct.

[Chroxvi]

I think this is ready for merge.