Config API edits

[rchinn1]

This pull request updates the src/api/config-api/index.md documentation to improve clarity, consistency, and user experience. The changes modernize the language, standardize formatting, and enhance the usability of reference links and instructions.

Documentation improvements:

• Rewrote introductory text and feature list for clearer, more concise language and consistent capitalization.
• Reformatted the API services table to use inline links with {:target="_blank"} for better accessibility and user experience.
• Updated section headings and instructions for consistency (e.g., "Quick Start" to "Quick start", "Access Tokens" to "Access tokens", etc.).
• Improved guidance around access tokens, including clearer warnings and updated contact information for support.
• Edited various sentences for grammar, style, and clarity throughout the document.

Proposed changes

Merge timing

Related issues (optional)

DOC-1262

[sade-wusi]

Looks good, just added periods to the ends of the bullets

[github-actions]

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