p2p: query seeds.wownero.com for seed nodes

The DNS seed list was empty, so the daemon never performed a lookup and
fell straight through to the hardcoded addresses. That left the only
bootstrap path baked into each binary: when three of the six hardcoded
seeds stopped answering, a fresh node on a lossy link could not find a
peer at all, and the failure reads as "disconnected from the network"
rather than as a seed problem.

A hostname lets us repoint the seed set without shipping a release. The
hardcoded addresses stay as the fallback for a node that cannot resolve
DNS, or one started with --no-dns-seed-nodes.

src/p2p/net_node.h

@@ -297,6 +297,7 @@ namespace nodetool
   private:
     const std::vector<std::string> m_seed_nodes_list =
     {
+      "seeds.wownero.com"
     };
 
     bool islimitup=false;