GHSA-3fxj-6jh8-hvhx: chi Has an IP Spoofing Vulnerability in `middleware.RealIP`

The RealIP middleware in go-chi/chi is vulnerable to IP spoofing because it blindly trusts the first (leftmost) element of the X-Forwarded-For HTTP header. This allows a remote attacker to bypass IP-based access control lists (ACLs) and rate-limiting mechanisms by providing a spoofed IP address in the header.