When Nginx is behind another proxy server (like CloudFlare or AWS ALB), the force-SSL
feature can cause redirect loops because Nginx sees the connection as plain HTTP
while SSL is already handled upstream. This adds a new boolean option to trust
the X-Forwarded-Proto header from upstream proxies.
Changes:
- Add `trust_forwarded_proto` column to proxy_host table (migration)
- Update model and API schema to support the new boolean field
- Modify force-ssl Nginx template to check X-Forwarded-Proto/X-Forwarded-Scheme
- Add map directives in nginx.conf to validate and sanitize forwarded headers
- Add advanced option toggle in frontend UI with i18n support (EN/ZH)
- Set proxy headers from validated map variables instead of $scheme
This allows administrators to control SSL redirect behavior when Nginx is deployed
behind a TLS-terminating proxy.
