Refactor rendering architecture and replace rasterizer with renderer

- Introduced SoftwareRenderer as a pixel-accurate software rendering backend.
- Removed the obsolete wolf_3d_rasterizer.dart file.
- Created a new wolf_3d_renderer.dart file to centralize rendering exports.
- Updated tests to accommodate the new rendering structure, including pushwall and projection sampling tests.
- Modified the WolfAsciiRenderer and WolfFlutterRenderer to utilize the new SoftwareRenderer.
- Enhanced enemy spawn tests to include new enemy states.

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

apps/wolf_3d_cli/lib/cli_game_loop.dart

@@ -6,9 +6,9 @@ import 'dart:io';
 
 import 'package:wolf_3d_dart/wolf_3d_engine.dart';
 import 'package:wolf_3d_dart/wolf_3d_input.dart';
-import 'package:wolf_3d_dart/wolf_3d_rasterizer.dart';
+import 'package:wolf_3d_dart/wolf_3d_renderer.dart';
 
-/// Runs the Wolf3D engine inside a terminal using CLI-specific rasterizers.
+/// Runs the Wolf3D engine inside a terminal using CLI-specific renderers.
 ///
 /// The loop owns raw-stdin handling, renderer switching, terminal size checks,
 /// and frame pacing. It expects [engine.input] to be a [CliInput] instance so
@@ -25,22 +25,22 @@ class CliGameLoop {
                'CliGameLoop requires a CliInput instance.',
              ),
 
-       primaryRasterizer = AsciiRasterizer(
-         mode: AsciiRasterizerMode.terminalAnsi,
+       primaryRenderer = AsciiRenderer(
+         mode: AsciiRendererMode.terminalAnsi,
        ),
-       secondaryRasterizer = SixelRasterizer() {
-    _rasterizer = primaryRasterizer;
+       secondaryRenderer = SixelRenderer() {
+    _renderer = primaryRenderer;
   }
 
   final WolfEngine engine;
-  final CliRasterizer primaryRasterizer;
-  final CliRasterizer secondaryRasterizer;
+  final CliRendererBackend primaryRenderer;
+  final CliRendererBackend secondaryRenderer;
   final CliInput input;
   final void Function(int code) onExit;
 
   final Stopwatch _stopwatch = Stopwatch();
   final Stream<List<int>> _stdinStream = stdin.asBroadcastStream();
-  late CliRasterizer _rasterizer;
+  late CliRendererBackend _renderer;
   StreamSubscription<List<int>>? _stdinSubscription;
   Timer? _timer;
   bool _isRunning = false;
@@ -52,9 +52,9 @@ class CliGameLoop {
       return;
     }
 
-    if (primaryRasterizer is SixelRasterizer) {
-      final sixel = primaryRasterizer as SixelRasterizer;
-      sixel.isSixelSupported = await SixelRasterizer.checkTerminalSixelSupport(
+    if (primaryRenderer is SixelRenderer) {
+      final sixel = primaryRenderer as SixelRenderer;
+      sixel.isSixelSupported = await SixelRenderer.checkTerminalSixelSupport(
         inputStream: _stdinStream,
       );
     }
@@ -116,11 +116,11 @@ class CliGameLoop {
     }
 
     if (bytes.contains(9)) {
-      // Tab swaps between rasterizers so renderer debugging stays available
+      // Tab swaps between renderers so renderer debugging stays available
       // without restarting the process.
-      _rasterizer = identical(_rasterizer, secondaryRasterizer)
-          ? primaryRasterizer
-          : secondaryRasterizer;
+      _renderer = identical(_renderer, secondaryRenderer)
+          ? primaryRenderer
+          : secondaryRenderer;
       stdout.write('\x1b[2J\x1b[H');
       return;
     }
@@ -136,7 +136,7 @@ class CliGameLoop {
     if (stdout.hasTerminal) {
       final int cols = stdout.terminalColumns;
       final int rows = stdout.terminalLines;
-      if (!_rasterizer.prepareTerminalFrame(
+      if (!_renderer.prepareTerminalFrame(
         engine,
         columns: cols,
         rows: rows,
@@ -145,7 +145,7 @@ class CliGameLoop {
         // game does not keep advancing while the user resizes the terminal.
         stdout.write('\x1b[2J\x1b[H');
         stdout.write(
-          _rasterizer.buildTerminalSizeWarning(columns: cols, rows: rows),
+          _renderer.buildTerminalSizeWarning(columns: cols, rows: rows),
         );
 
         _lastTick = _stopwatch.elapsed;
@@ -160,6 +160,6 @@ class CliGameLoop {
     stdout.write('\x1b[H');
 
     engine.tick(elapsed);
-    stdout.write(_rasterizer.render(engine));
+    stdout.write(_renderer.render(engine));
   }
 }