mealie: DNS-Rebinding TOCTOU in SSRF Guard Allows Internal Network and Cloud Metadata Access

Mealie's AsyncSafeTransport SSRF guard (mealie/pkgs/safehttp/transport.py) resolves a target hostname once, checks the resolved IP against private-range rules, but then issues the actual outbound HTTP request using the original hostname, which the underlying async transport re-resolves independently. Because the validated IP is never pinned to the actual connection, a DNS-rebinding attacker (returning a public IP to the validation lookup and a private/metadata IP to the real connection) defeats the guard. This is reachable by any authenticated user via /api/recipes/create/url, /api/recipes/test-scrape-url, and /api/recipes/{slug}/image, and the scraper reflects fetched content back to the requester, allowing an authenticated user to read internal HTTP services and cloud-metadata endpoints.