Better aligning GitHub docs with archetype docs on Experience League

[bohnertchris]

Description

There is currently a lot of overlap and redundancy in the documentation for the archetype within the readmes of this repository and that on Experience League (https://experienceleague.adobe.com/docs/experience-manager-core-components/using/developing/archetype/overview.html).

This PR and another in the Core Components documentation repo aims to limit the documentation on Experience League to a usage overview and general information about the archetype while all technical details remain in the GitHub readmes.

Related Issue

CQDOC-20146
PR # 262 on the experience-manager-core-components.en corporate repo

Motivation and Context

With this change, updates to the archetype only need to be updated in the readmes, minimizing the possibility of inconsistencies arising in the two documentation sources. It also makes it clearer to the user what is documented where.

How Has This Been Tested?

No. I only made changes to readmes.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.