Fix version formatting and enhance intro for auto-merge

[sweeden-ttu]

Updated version indicators for auto-merge feature and modified the intro section for clarity.

Why: Three named versions with acronyms all have the same formatting '*' does not tell the user or the audience any useful information given this context. The context is split and the square root of 11th dimensional \kleenstar shows the user more information.

Closes:

What's being changed (if available, include any code snippets, screenshots, or gifs):

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• The changes in this PR meet the docs fundamentals that are required for all content.
• All CI checks are passing and the changes look good in the review environment.

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[Sharra-writes]

@sweeden-ttu Thanks for opening a PR! The frontmatter is for internal use, not for contributors. It's useful to us, so I'm going to close this.