[mesudip]

Moves the frontend and docs images from nginx 1.28 to 1.30, the current stable line. The devnet's prebuilt frontend image follows the frontend.

List of changes

• Change: the frontend image uses nginx 1.30 (with brotli) instead of 1.28
• Change: the docs image uses nginx 1.30 instead of 1.28
• Change: the devnet's prebuilt frontend image follows the frontend

Checked locally: the new frontend image serves the app, compressed responses, missing pages and the maintenance page as before, and the docs image serves the site.

Checklist

• related issue
• My changes generate no new warnings
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the changelog
• I have added tests that prove my fix is effective or that my feature works