Make README.md more friendly

[mntrngh]

Pull Request

Title

Describe steps to run script more precise and add some user-friendly notes in the documentation.

Type of Change

• New feature
• Bug fix
• Documentation update
• Refactoring
• Hotfix
• Security patch
• UI/UX improvement

Description

I believe there's a little bit of confusion for not tech-savvy people in the phrase "run with PowerShell or Windows Terminal" and it just makes no sense because opening Windows Terminal will get you to the actual PowerShell prompt.
And some people may be not sure of what branch of the script they better run, stable or dev, so I mentioned stable branch as a recommended.

Impact

More user-friendly experience for not tech-savvy people.

Additional Information

I'd like to make an another commit mentioning that you don't need the last iteration of PowerShell and you will be ok with just the default built-in "Windows PowerShell", but I'm not sure how to describe it the best and what's the oldest version possible which's able to run the script.

Checklist

• My code adheres to the coding and style guidelines of the project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no errors/warnings/merge conflicts.