[FEATURE] Need "Contributing" documentation for Python scripts

### Is your feature request related to a problem? Please describe.

I had a problem after submitting a PR with a Python script due to a)my non-existent experience of Python and b) no guidelines on the style (and style checkers) needed for scripts.

### Describe the solution you'd like

Having grappled with Python for the first time and submitting a [PR](https://github.com/apache/nuttx/pull/16257) with a script...finding it failed CI despited running checkpatch.sh...then finding I needed `black`, `isort` and `flake8` installed...and then finding I needed to actually format my code using `black` before running the checks...and breath...

I think some guidelines for Python script contributions might be in order (unless I missed them).

Since I am totally new to Python I don't think I'm best qualified to do this.

Can anyone oblige?

### Describe alternatives you've considered

_No response_

### Verification

- [x] I have verified before submitting the report.

The request concerns contribution guidance for Python scripts and names black, isort, flake8, and checkpatch.sh as relevant tools. Start by locating the repository's existing contributing documentation and Python-script checks. Done means contributors can find the required style, formatter, and checker steps before submitting a PR.

Written by the indexing model from the issue text.