feat(ground-suite): add replay observability console

ground-suite/test/core/transport/replay_vehicle_data_port_test.dart

@@ -0,0 +1,30 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:ground_suite/core/observations/observed_event.dart';
+import 'package:ground_suite/core/observations/vehicle_data_update.dart';
+import 'package:ground_suite/core/transport/replay_vehicle_data_port.dart';
+
+void main() {
+  test('replay covers identity, telemetry, log, error, and shutdown', () async {
+    const port = ReplayVehicleDataPort();
+
+    final events = [
+      for (final update in await port.observe().toList())
+        if (update case ObservationReceived(:final event)) event,
+    ];
+
+    expect(events.whereType<HeartbeatEvent>(), hasLength(1));
+    expect(events.whereType<TelemetryEvent>(), hasLength(2));
+    final logs = events.whereType<LogEvent>().toList();
+    final errors = events.whereType<ErrorEvent>().toList();
+    expect(logs, hasLength(2));
+    expect(errors, hasLength(1));
+    expect(events.whereType<ShutdownEvent>(), hasLength(1));
+    expect(logs.first.isCoalesced, isTrue);
+    expect(errors.single.isTruncated, isTrue);
+  });
+
+  test('unknown wire enum values remain visible', () {
+    expect(const MavSeverity(99).label, 'Unknown (99)');
+    expect(const KaptanShutdownReason(99).label, 'Unknown (99)');
+  });
+}