Prefer QUIC fabric endpoints

agents/rap-node-agent/internal/mesh/endpoint_candidate_scoring.go

@@ -59,6 +59,9 @@ func scorePeerEndpointCandidate(candidate PeerEndpointCandidate, opts EndpointCa
 	reasons := []string{"base"}
 
 	switch candidate.Transport {
+	case "quic", "direct_quic", "udp_quic", "quic_udp":
+		score += 45
+		reasons = append(reasons, "transport:quic")
 	case "direct_tcp_tls", "direct_http", "direct_https":
 		score += 35
 		reasons = append(reasons, "transport:direct")

agents/rap-node-agent/internal/mesh/endpoint_candidate_scoring_test.go

@@ -99,6 +99,45 @@ func TestRankPeerEndpointCandidatesUsesDeterministicTieBreak(t *testing.T) {
 	}
 }
 
+func TestRankPeerEndpointCandidatesPrefersQUICFastPath(t *testing.T) {
+	now := time.Date(2026, 5, 16, 12, 0, 0, 0, time.UTC)
+	candidates := []PeerEndpointCandidate{
+		{
+			EndpointID:       "node-b-wss",
+			NodeID:           "node-b",
+			Transport:        "wss",
+			Address:          "wss://node-b.example.test",
+			Reachability:     "public",
+			NATType:          "none",
+			ConnectivityMode: "direct",
+			Priority:         10,
+			LastVerifiedAt:   &now,
+		},
+		{
+			EndpointID:       "node-b-quic",
+			NodeID:           "node-b",
+			Transport:        "direct_quic",
+			Address:          "quic://node-b.example.test:19443",
+			Reachability:     "public",
+			NATType:          "none",
+			ConnectivityMode: "direct",
+			Priority:         10,
+			LastVerifiedAt:   &now,
+		},
+	}
+	ranked := RankPeerEndpointCandidates(candidates, EndpointCandidateScoreOptions{
+		ChannelClass:       SyntheticChannelFabricControl,
+		Now:                now,
+		MaxVerificationAge: time.Minute,
+	})
+	if ranked[0].Candidate.EndpointID != "node-b-quic" {
+		t.Fatalf("top endpoint = %q, want quic: %+v", ranked[0].Candidate.EndpointID, ranked)
+	}
+	if !containsReason(ranked[0].Reasons, "transport:quic") {
+		t.Fatalf("quic reason missing: %+v", ranked[0].Reasons)
+	}
+}
+
 func TestRankPeerEndpointCandidatesPrefersCorporatePrivateEndpoint(t *testing.T) {
 	now := time.Date(2026, 4, 28, 12, 0, 0, 0, time.UTC)
 	candidates := []PeerEndpointCandidate{