The hive-matrix nixos-container came up with an EMPTY /etc/resolv.conf
even with networking.nameservers set, so tuwunel hard-failed at boot
(no nameservers found). The nixos-container default useHostResolvConf=true
puts in-container resolvconf in host-tracking mode: it ignores
networking.nameservers and never receives the host resolv.conf across the
shared-netns boundary, so resolvconf regenerates an empty file.
When the hive network module is on, turn off host-tracking (mkForce, to
beat the module default) so resolvconf honours networking.nameservers,
pointing the resolver at the gateway-container dnsmasq at bridgeIp.
Network module off -> inherit the host resolv.conf.
812a072e1c