arrow

GH-41105: [Python][Docs] Update PyArrow installation docs for conda package split (#41135)

Do not merge until some discussion is had about how to time this relative to https://github.com/conda-forge/arrow-cpp-feedstock/pull/1376. Additionally, consider hot-patching this into arrow-site if appropriate.

### What changes are included in this PR?

Updates to the [Python installation docs](https://arrow.apache.org/docs/python/install.html) to reflect the in-progress change splitting PyArrow on conda-forge into three separate packages. Specifically:

1. Add a note in the conda section highlighting that there are three packages and linking to a new section (2) in order to provide more information
2. Add a new section, linked from (1), providing a comparison of each package as a table

### Are these changes tested?

These are just docs changes. I have built them locally and they look fine.

### Are there any user-facing changes?

Just docs.
* GitHub Issue: #41105

Lead-authored-by: Bryce Mecum <petridish@gmail.com>
Co-authored-by: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Signed-off-by: Bryce Mecum <petridish@gmail.com>