Reverse proxy for the Familienarchiv host, validated against Caddy 2.
Includes both vhosts (production and staging), the Gitea vhost, and:
- HSTS, X-Content-Type-Options, Referrer-Policy headers on every site
- "-Server" header strip to hide the Caddy version
- /actuator/* responds 404 on both archive vhosts (defense in depth
for Spring Boot's management endpoints)
X-Frame-Options is intentionally not set in Caddy: Spring Security
configures frame-options SAMEORIGIN for the in-app PDF preview
iframe; a DENY header here would conflict.
Refs #497.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>