feat(front): 프론트 화면 개선 및 설정 저장소 추가

- front_screen_animation.dart: 프론트 화면 애니메이션 추가
- settings_repository.dart: 설정 저장소 구현
- front/widgets/: 프론트 화면 위젯 분리
- mobile_carousel_layout.dart: 모바일 레이아웃 개선
- app.dart: 앱 설정 개선
- game_text_l10n.dart: 텍스트 추가

lib/src/features/front/widgets/hero_vs_boss_animation.dart

@@ -0,0 +1,169 @@
+import 'dart:async';
+import 'dart:math';
+
+import 'package:flutter/material.dart';
+
+import 'package:askiineverdie/src/core/animation/front_screen_animation.dart';
+
+/// 프론트 화면용 Hero vs Glitch God ASCII 애니메이션 위젯
+///
+/// 작은 용사가 거대한 Glitch God에 맞서는 루프 애니메이션
+/// 항상 검은 배경에 흰색 텍스트, 특수 효과만 컬러로 표시
+class HeroVsBossAnimation extends StatefulWidget {
+  const HeroVsBossAnimation({super.key});
+
+  @override
+  State<HeroVsBossAnimation> createState() => _HeroVsBossAnimationState();
+}
+
+class _HeroVsBossAnimationState extends State<HeroVsBossAnimation> {
+  int _currentFrame = 0;
+  Timer? _timer;
+  final Random _random = Random();
+
+  @override
+  void initState() {
+    super.initState();
+    _startAnimation();
+  }
+
+  @override
+  void dispose() {
+    _timer?.cancel();
+    super.dispose();
+  }
+
+  void _startAnimation() {
+    _timer = Timer.periodic(
+      const Duration(milliseconds: frontScreenAnimationIntervalMs),
+      (_) {
+        if (mounted) {
+          setState(() {
+            _currentFrame =
+                (_currentFrame + 1) % frontScreenAnimationFrameCount;
+          });
+        }
+      },
+    );
+  }
+
+  /// 글리치 효과: 랜덤 문자 대체
+  String _applyGlitchEffect(String frame) {
+    // 10% 확률로 글리치 효과 적용
+    if (_random.nextDouble() > 0.1) return frame;
+
+    const glitchChars = '@#\$%&*!?~';
+    final chars = frame.split('');
+    final glitchCount = _random.nextInt(5) + 1;
+
+    for (var i = 0; i < glitchCount; i++) {
+      final pos = _random.nextInt(chars.length);
+      if (chars[pos] != ' ' && chars[pos] != '\n') {
+        chars[pos] = glitchChars[_random.nextInt(glitchChars.length)];
+      }
+    }
+
+    return chars.join();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final frame = _applyGlitchEffect(
+      frontScreenAnimationFrames[_currentFrame],
+    );
+
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 16),
+      decoration: BoxDecoration(
+        // 항상 검은 배경
+        color: Colors.black,
+        borderRadius: BorderRadius.circular(12),
+        border: Border.all(
+          color: Colors.white24,
+          width: 1,
+        ),
+        // 은은한 글로우 효과
+        boxShadow: [
+          BoxShadow(
+            color: Colors.cyan.withValues(alpha: 0.15),
+            blurRadius: 20,
+            spreadRadius: 2,
+          ),
+        ],
+      ),
+      child: Column(
+        children: [
+          // ASCII 애니메이션 (흰색 텍스트)
+          FittedBox(
+            fit: BoxFit.scaleDown,
+            child: Text(
+              frame,
+              style: const TextStyle(
+                fontFamily: 'JetBrainsMono',
+                fontSize: 10,
+                height: 1.1,
+                color: Colors.white,
+                letterSpacing: 0,
+              ),
+            ),
+          ),
+          const SizedBox(height: 8),
+          // 하단 효과 바 (컬러)
+          _buildEffectBar(),
+        ],
+      ),
+    );
+  }
+
+  /// 하단 효과 바: 글리치/전투 효과 시각화
+  Widget _buildEffectBar() {
+    // 프레임에 따라 색상 변화
+    final colors = [
+      Colors.cyan,
+      Colors.purple,
+      Colors.red,
+      Colors.cyan,
+      Colors.yellow,
+      Colors.purple,
+    ];
+    final currentColor = colors[_currentFrame % colors.length];
+
+    return Row(
+      mainAxisAlignment: MainAxisAlignment.center,
+      children: [
+        // 왼쪽 검 아이콘 (용사)
+        Icon(
+          Icons.flash_on,
+          size: 14,
+          color: Colors.yellow.withValues(alpha: 0.8),
+        ),
+        const SizedBox(width: 8),
+        // 중앙 효과 바
+        Expanded(
+          child: Container(
+            height: 3,
+            decoration: BoxDecoration(
+              gradient: LinearGradient(
+                colors: [
+                  Colors.transparent,
+                  currentColor.withValues(alpha: 0.7),
+                  Colors.white.withValues(alpha: 0.9),
+                  currentColor.withValues(alpha: 0.7),
+                  Colors.transparent,
+                ],
+              ),
+              borderRadius: BorderRadius.circular(2),
+            ),
+          ),
+        ),
+        const SizedBox(width: 8),
+        // 오른쪽 보스 아이콘
+        Icon(
+          Icons.whatshot,
+          size: 14,
+          color: Colors.red.withValues(alpha: 0.8),
+        ),
+      ],
+    );
+  }
+}