Address several optional feature issues

[labkey-adam]

Rationale

This addresses four separate "optional feature" requests:

• https://github.com/LabKey/internal-issues/issues/1347
• https://github.com/LabKey/internal-issues/issues/1349
• https://github.com/LabKey/internal-issues/issues/1344
• https://github.com/LabKey/internal-issues/issues/1348

Note that making the "Disable enforce CSP" flag deprecated means setting it will cause an admin warning to be displayed. I think that's fine, but worth pointing out.

Tasks

• Claude Code Review
• Code Review
• TeamCity Review and Merge
• User Education Handoff
  • Changes to this docs page https://www.labkey.org/Documentation/wiki-page.view?name=experimental
    • Adjust the "Optional Features" top-level description to match the new, more encouraging text in the product. Or remove this line since it's redundant with the product text.
    • Move "No Guest Account" to the "Optional Features" section
    • Move "Disable enforce CSP" to the "Deprecated Features" section
    • Remove "Generic [details] link"
  • The only "Release Note" that seems worthwhile is to mention that checking "Disable enforce CSP" will now cause an admin warning
• Verify Fix @labkey-hannah