feat(go): reuse parsed fields across projections

go/vehicle-gateway/internal/realtime/repository_test.go

@@ -646,6 +646,37 @@ func TestRepositoryOnlineStatus(t *testing.T) {
 	}
 }
 
+func TestRepositoryUsesEnvelopeParsedFieldsForRealtimeKV(t *testing.T) {
+	repo, closeFn := newTestRepository(t)
+	defer closeFn()
+	ctx := context.Background()
+
+	if err := repo.Update(ctx, envelope.FrameEnvelope{
+		Protocol:     envelope.ProtocolJT808,
+		VIN:          "VIN001",
+		EventTimeMS:  1000,
+		ReceivedAtMS: 1100,
+		MessageID:    "0x0200",
+		Parsed: map[string]any{
+			"location": map[string]any{"speed_kmh": 99},
+		},
+		ParsedFields: map[string]any{
+			"jt808.location.speed_kmh": "12.3",
+		},
+		Fields: map[string]any{envelope.FieldSpeedKMH: 12.3},
+	}); err != nil {
+		t.Fatalf("Update() error = %v", err)
+	}
+
+	values, err := repo.client.HGetAll(ctx, realtimeKVValuesKey(envelope.ProtocolJT808, "VIN001")).Result()
+	if err != nil {
+		t.Fatalf("HGetAll() error = %v", err)
+	}
+	if got, want := values["jt808.location.speed_kmh"], "12.3"; got != want {
+		t.Fatalf("speed kv = %#v, want %q; all=%#v", got, want, values)
+	}
+}
+
 func TestRepositorySkipsFramesWithoutVIN(t *testing.T) {
 	repo, closeFn := newTestRepository(t)
 	defer closeFn()