fix: align channel copy and gateway connection state

gateway/internal/upstream/connection_loss_test.go

@@ -1,14 +1,26 @@
 package upstream
 
 import (
+	"context"
 	"errors"
 	"testing"
 )
 
 func TestHandleConnectionLossNotifiesPendingSubmitters(t *testing.T) {
+	var reported ConnectionState
 	conn := &connection{
 		pending: make(map[uint32]chan submitPartResponse),
+		pool: &connectionPool{
+			channelID:    "channel-1",
+			connectionID: "channel-1:primary",
+			config:       normalizeUpstreamConfig(queueUpstreamConfigForTest()),
+			reporter: func(_ context.Context, state ConnectionState) error {
+				reported = state
+				return nil
+			},
+		},
 	}
+	conn.pool.conns = []*connection{conn}
 	waiter := make(chan submitPartResponse, 1)
 	conn.pending[7] = waiter
 
@@ -30,6 +42,9 @@ func TestHandleConnectionLossNotifiesPendingSubmitters(t *testing.T) {
 	if len(conn.pending) != 0 {
 		t.Fatalf("expected pending map to be reset, got %d entries", len(conn.pending))
 	}
+	if reported.Status != "disconnected" || reported.CurrentConnections != 0 {
+		t.Fatalf("unexpected reported state: %+v", reported)
+	}
 }
 
 func TestTemporaryReadTimeoutDetection(t *testing.T) {