DoH-only sequential upstreams made first-time lookups slow. Add plain
UDP 1.1.1.1/9.9.9.9 alongside DoH and set upstream_mode=parallel so
AdGuard queries all four simultaneously and uses the fastest response.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
New services/adguard.nix runs AdGuard Home on the mediaserver with DoH
upstreams (Cloudflare + Quad9) and three default blocklists. DNS listens
on :53; web UI on 127.0.0.1:3000, reverse-proxied at adguard.nordhammer.it.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
