Fix west installation of scaffold

[MilhoNerfado]

This pull request updates the project's dependencies and configuration files to improve package management and development workflows. The most important changes are grouped below:

Dependency management improvements:

• Added the rich library as a required dependency in pyproject.toml.
• Introduced an optional dev dependency group in pyproject.toml with ruff and pytest for development and testing.

Build and requirements file updates:

• Removed the editable install of the scaffold tool from requirements-west.txt, likely to avoid redundancy or conflicts.
• Updated the zephyr/module.yml configuration to use requirements.txt instead of requirements-west.txt for pip dependencies, aligning with standard practices.

[gemini-code-assist]

Code Review

This pull request updates dependency management by modifying pyproject.toml and requirements.txt, and redirecting the Zephyr module configuration. Feedback identifies duplicated and potentially invalid versioning for the rich library in both dependency files. Additionally, development dependencies like ruff and pytest should be removed from requirements.txt to prevent unnecessary installations for end-users.

[gemini-code-assist]

The rich dependency is duplicated at lines 9 and 14. Furthermore, version 15.0 appears to be incorrect as the current stable version of rich is 13.x. This will likely cause installation to fail. Please remove the duplicate and verify the required version.

Suggested change

	"rich>=13.0",
	"jinja2>=3.1",
	"platformdirs>=4.0",
	"pyyaml>=6.0",
	"jsonschema>=4.18",
	"rich>=15.0",
	"rich>=13.0",
	"jinja2>=3.1",
	"platformdirs>=4.0",
	"pyyaml>=6.0",
	"jsonschema>=4.18",

[gemini-code-assist]

The rich dependency is duplicated here as well. It is recommended to keep only one entry with the correct version constraint.

rich>=13.0
jinja2>=3.1
platformdirs>=4.0
pyyaml>=6.0
jsonschema>=4.18

[gemini-code-assist]

Development dependencies (ruff and pytest) should not be included in the main requirements.txt file, as this file is used for the Zephyr module installation via west. These are already defined in the dev section of pyproject.toml. Including them here forces end-users to install unnecessary development tools.