Refactor menu rendering and improve projection sampling

- Updated AsciiRasterizer to support game and episode selection menus with improved layout and cursor handling.
- Enhanced SixelRasterizer and SoftwareRasterizer to modularize menu drawing logic for game and episode selection.
- Introduced new methods for drawing menus and applying fade effects across rasterizers.
- Adjusted wall texture sampling in Rasterizer to anchor to projection height center for consistent rendering.
- Added tests for wall texture sampling behavior to ensure legacy compatibility and new functionality.
- Modified Flutter audio adapter to use nullable access for active game and adjusted game selection logic in the main class.
- Cleaned up input handling in Wolf3dFlutterInput by removing unused menu tap variables.

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

packages/wolf_3d_dart/test/engine/audio_events_test.dart

@@ -147,7 +147,7 @@ WolfEngine _buildEngine({
     startingEpisode: 0,
     frameBuffer: FrameBuffer(64, 64),
     input: input,
-    audio: audio,
+    engineAudio: audio,
     onGameWon: () {},
   );
 }

packages/wolf_3d_dart/test/rasterizer/projection_sampling_test.dart

@@ -0,0 +1,85 @@
+import 'package:test/test.dart';
+import 'package:wolf_3d_dart/src/rasterizer/rasterizer.dart';
+import 'package:wolf_3d_dart/wolf_3d_data_types.dart';
+import 'package:wolf_3d_dart/wolf_3d_engine.dart';
+
+void main() {
+  group('Rasterizer wall texture sampling', () {
+    test('anchors wall texel sampling to projection height center', () {
+      final rasterizer = _TestRasterizer(customProjectionViewHeight: 40);
+      rasterizer.configureViewGeometry(width: 64, height: 64, viewHeight: 20);
+
+      // With sceneHeight=40 and columnHeight=20, projected wall spans y=10..30.
+      // Top pixel should sample from top texel row.
+      expect(rasterizer.wallTexY(10, 20), 0);
+
+      // Bottom visible pixel should sample close to bottom texel row.
+      expect(rasterizer.wallTexY(29, 20), inInclusiveRange(60, 63));
+    });
+
+    test('keeps legacy behavior when projection height equals view height', () {
+      final rasterizer = _TestRasterizer(customProjectionViewHeight: 20);
+      rasterizer.configureViewGeometry(width: 64, height: 64, viewHeight: 20);
+
+      // With sceneHeight=viewHeight=20 and columnHeight=20, top starts at y=0.
+      expect(rasterizer.wallTexY(0, 20), 0);
+      expect(rasterizer.wallTexY(19, 20), inInclusiveRange(60, 63));
+    });
+  });
+}
+
+class _TestRasterizer extends Rasterizer<FrameBuffer> {
+  _TestRasterizer({required this.customProjectionViewHeight});
+
+  final int customProjectionViewHeight;
+
+  @override
+  int get projectionViewHeight => customProjectionViewHeight;
+
+  void configureViewGeometry({
+    required int width,
+    required int height,
+    required int viewHeight,
+  }) {
+    this.width = width;
+    this.height = height;
+    this.viewHeight = viewHeight;
+  }
+
+  @override
+  void prepareFrame(WolfEngine engine) {}
+
+  @override
+  void drawWallColumn(
+    int x,
+    int drawStart,
+    int drawEnd,
+    int columnHeight,
+    Sprite texture,
+    int texX,
+    double perpWallDist,
+    int side,
+  ) {}
+
+  @override
+  void drawSpriteStripe(
+    int stripeX,
+    int drawStartY,
+    int drawEndY,
+    int spriteHeight,
+    Sprite texture,
+    int texX,
+    double transformY,
+  ) {}
+
+  @override
+  void drawWeapon(WolfEngine engine) {}
+
+  @override
+  void drawHud(WolfEngine engine) {}
+
+  @override
+  FrameBuffer finalizeFrame() {
+    return FrameBuffer(1, 1);
+  }
+}