feat: Implement packaged games loading and update engine initialization to support seeded games

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

apps/wolf_3d_gui/test/game_data_picker_manager_test.dart

@@ -53,6 +53,7 @@ class _RecordingEngine extends Wolf3dFlutterEngine {
   Future<Wolf3dFlutterEngine> init({
     String? directory,
     Iterable<String>? additionalDirectories,
+    Iterable<WolfensteinData>? seededGames,
   }) async {
     initCallCount++;
     lastDirectory = directory;

apps/wolf_3d_gui/test/packaged_games_loader_test.dart

@@ -0,0 +1,91 @@
+import 'dart:typed_data';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:wolf_3d_dart/wolf_3d_data_types.dart';
+import 'package:wolf_3d_gui/packaged_games_loader.dart';
+
+void main() {
+  group('loadPackagedGames', () {
+    test('loads known packaged directories in order', () async {
+      final requested = <(GameVersion, String)>[];
+
+      final games = await loadPackagedGames(
+        loader: ({required version, required assetDirectory}) async {
+          requested.add((version, assetDirectory));
+          return _buildTestData(version);
+        },
+      );
+
+      expect(requested, <(GameVersion, String)>[
+        (GameVersion.retail, 'assets/retail'),
+        (GameVersion.shareware, 'assets/shareware'),
+        (GameVersion.spearOfDestinyDemo, 'assets/sod/shareware'),
+      ]);
+      expect(games.map((g) => g.version), <GameVersion>[
+        GameVersion.retail,
+        GameVersion.shareware,
+        GameVersion.spearOfDestinyDemo,
+      ]);
+    });
+
+    test('skips failing packaged loads and keeps successful ones', () async {
+      final games = await loadPackagedGames(
+        loader: ({required version, required assetDirectory}) async {
+          if (version == GameVersion.shareware) {
+            throw Exception('shareware unavailable');
+          }
+          return _buildTestData(version);
+        },
+      );
+
+      expect(games.map((g) => g.version), <GameVersion>[
+        GameVersion.retail,
+        GameVersion.spearOfDestinyDemo,
+      ]);
+    });
+  });
+}
+
+WolfensteinData _buildTestData(GameVersion version) {
+  final wallGrid = List.generate(64, (_) => List.filled(64, 0));
+  final objectGrid = List.generate(64, (_) => List.filled(64, 0));
+
+  for (int i = 0; i < 64; i++) {
+    wallGrid[0][i] = 2;
+    wallGrid[63][i] = 2;
+    wallGrid[i][0] = 2;
+    wallGrid[i][63] = 2;
+  }
+  objectGrid[2][2] = MapObject.playerEast;
+
+  return WolfensteinData(
+    version: version,
+    dataVersion: DataVersion.unknown,
+    registry: version == GameVersion.shareware
+        ? SharewareAssetRegistry()
+        : RetailAssetRegistry(),
+    walls: <Sprite>[_sprite(1), _sprite(1), _sprite(2), _sprite(2)],
+    sprites: List<Sprite>.generate(436, (_) => _sprite(255)),
+    sounds: List<PcmSound>.generate(200, (_) => PcmSound(Uint8List(1))),
+    adLibSounds: const <PcmSound>[],
+    music: const <ImfMusic>[],
+    vgaImages: const <VgaImage>[],
+    episodes: <Episode>[
+      Episode(
+        name: 'Test Episode',
+        levels: <WolfLevel>[
+          WolfLevel(
+            name: 'Test Level',
+            wallGrid: wallGrid,
+            areaGrid: List.generate(64, (_) => List.filled(64, -1)),
+            objectGrid: objectGrid,
+            music: Music.level01,
+          ),
+        ],
+      ),
+    ],
+  );
+}
+
+Sprite _sprite(int color) =>
+    Sprite(Uint8List.fromList(List<int>.filled(64 * 64, color)));

apps/wolf_3d_gui/test/wolf3d_gui_app_test.dart

@@ -88,6 +88,7 @@ class _RecordingEngine extends Wolf3dFlutterEngine {
   Future<Wolf3dFlutterEngine> init({
     String? directory,
     Iterable<String>? additionalDirectories,
+    Iterable<WolfensteinData>? seededGames,
   }) async {
     initCallCount++;
     availableGames