Skip ACME DNS propagation check for local resolver caching

Local DNS resolver caches stale responses causing the wildcard
cert DNS-01 challenge to time out before propagation is confirmed.
Cloudflare's authoritative servers propagate fast enough for
Let's Encrypt to validate without the client-side check.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

services/nginx.nix

@@ -62,6 +62,7 @@ in
         domain = "*.nordhammer.it";
         extraDomainNames = [ "nordhammer.it" ];
         dnsProvider = "cloudflare";
+        dnsPropagationCheck = false;
         credentialFiles = {
           "CF_DNS_API_TOKEN_FILE" = "/var/secrets/cloudflare-token";
         };