AWS prescriptive-guidance documentation change
Summary
Renamed file from welcome.md to introduction.md and updated internal references. Removed author affiliations, document history, and one related content link. Corrected multiple URL paths by removing double slashes and updated external resource links.
Security assessment
Changes involve routine documentation maintenance (renaming, link corrections, content pruning). No security vulnerabilities, patches, or security features are mentioned. The polyglot persistence link update points to AWS documentation but doesn't introduce security content.