docs: add 1.2.0 server release notes

[blue4209211]

Summary

1.2.0 release

Type of change

• Typo / minor wording fix
• New documentation page
• Update to existing documentation
• Build, CI, or tooling change
• Other (please describe)

Checklist

• I ran npm run build locally and the site builds without errors
• I ran npm run lint locally and lint passes
• Internal links work; new external links open the correct page
• My commits are signed off (DCO — git commit -s)
• I read CONTRIBUTING.md

Screenshots (if visual changes)

n/a

Additional notes

n/a

[gemini-code-assist]

Code Review

This pull request adds the release notes for version 1.2.0 and updates the release index page to include links to the v1.2.0 and v1.1.0 release notes. Feedback on the release notes document includes adding a main H1 heading for the version title to ensure proper rendering and renaming the 'Troubleshoot' section to 'Troubleshooting' to maintain consistency with other category headings.