Serve uploaded SVGs (admin logos etc.) with a restrictive
Content-Security-Policy (default-src 'none'; style-src 'unsafe-inline';
img-src 'self' data:) + X-Content-Type-Options: nosniff in secureStatic.
The browser still renders the vector, but any embedded <script>/on*
handler can't execute if the SVG is opened directly — keeps real SVGs
(scalable) instead of rasterising them. Applies to all secureStatic
mounts (uploads/photos/thumbnails/fonts); only SVGs get the header.