API doesn't detect reverse proxy with SSL termination

### Kyoo's version master ### What happened? Currently, with Kyoo v5, the pagingation API returns incorrect next/this URLs when Kyoo is behind a reverse proxy that terminates the SSL connection. The API sends HTTP URLs and the browser doesn't want to query them: ``` Mixed Content: The page at 'https://kyoo.domain.tld/browse' was loaded over HTTPS, but requested an insecure resource 'http://kyoo.domain.tld/api/shows?sort=name&filter=&query=&after=...'. This request has been blocked; the content must be served over HTTPS. ``` I see two ways of solving this, the API, in order to send the right url, should either: - use the `X-Forwarded-Proto` header - use a base URL in the API defined via an environment variable