feat: 글래스모피즘 디자인 시스템 및 색상 가이드 전면 적용

- @doc/color.md 가이드라인에 따른 색상 시스템 전면 개편
- 딥 블루(#2563EB), 스카이 블루(#60A5FA) 메인 컬러로 변경
- 모든 화면과 위젯에 글래스모피즘 효과 일관성 있게 적용
- darkNavy, navyGray 등 새로운 텍스트 색상 체계 도입
- 공통 스낵바 및 다이얼로그 컴포넌트 추가
- Claude AI 프로젝트 컨텍스트 파일(CLAUDE.md) 추가

영향받은 컴포넌트:
- 10개 스크린 (main, settings, detail, splash 등)
- 30개 이상 위젯 (buttons, cards, forms 등)
- 테마 시스템 (AppColors, AppTheme)

🤖 Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

lib/widgets/add_subscription/add_subscription_app_bar.dart

@@ -26,11 +26,11 @@ class AddSubscriptionAppBar extends StatelessWidget implements PreferredSizeWidg
 
     return Container(
       decoration: BoxDecoration(
-        color: Colors.white.withOpacity(appBarOpacity),
+        color: Colors.white.withValues(alpha: appBarOpacity),
         boxShadow: appBarOpacity > 0.6
             ? [
                 BoxShadow(
-                  color: Colors.black.withOpacity(0.1 * appBarOpacity),
+                  color: Colors.black.withValues(alpha: 0.1 * appBarOpacity),
                   spreadRadius: 1,
                   blurRadius: 8,
                   offset: const Offset(0, 4),
@@ -51,7 +51,7 @@ class AddSubscriptionAppBar extends StatelessWidget implements PreferredSizeWidg
               shadows: appBarOpacity > 0.6
                   ? [
                       Shadow(
-                        color: Colors.black.withOpacity(0.2),
+                        color: Colors.black.withValues(alpha: 0.2),
                         offset: const Offset(0, 1),
                         blurRadius: 2,
                       )

lib/widgets/add_subscription/add_subscription_event_section.dart

@@ -44,7 +44,7 @@ class AddSubscriptionEventSection extends StatelessWidget {
             border: Border.all(
               color: controller.isEventActive 
                   ? const Color(0xFF3B82F6) 
-                  : Colors.grey.withOpacity(0.2),
+                  : Colors.grey.withValues(alpha: 0.2),
               width: controller.isEventActive ? 2 : 1,
             ),
           ),

lib/widgets/add_subscription/add_subscription_form.dart

@@ -297,7 +297,7 @@ class _CurrencyOption extends StatelessWidget {
           decoration: BoxDecoration(
             color: isSelected 
                 ? const Color(0xFF3B82F6)
-                : Colors.grey.withOpacity(0.1),
+                : Colors.grey.withValues(alpha: 0.1),
             borderRadius: BorderRadius.circular(12),
           ),
           child: Center(
@@ -350,7 +350,7 @@ class _BillingCycleSelector extends StatelessWidget {
                 decoration: BoxDecoration(
                   color: isSelected 
                       ? gradientColors[0]
-                      : Colors.grey.withOpacity(0.1),
+                      : Colors.grey.withValues(alpha: 0.1),
                   borderRadius: BorderRadius.circular(12),
                 ),
                 child: Text(
@@ -402,14 +402,14 @@ class _CategorySelector extends StatelessWidget {
             decoration: BoxDecoration(
               color: isSelected 
                   ? gradientColors[0]
-                  : Colors.grey.withOpacity(0.1),
+                  : Colors.grey.withValues(alpha: 0.1),
               borderRadius: BorderRadius.circular(12),
             ),
             child: Row(
               mainAxisSize: MainAxisSize.min,
               children: [
                 Text(
-                  category.emoji,
+                  category.icon,
                   style: const TextStyle(fontSize: 16),
                 ),
                 const SizedBox(width: 6),

lib/widgets/add_subscription/add_subscription_header.dart

@@ -32,7 +32,7 @@ class AddSubscriptionHeader extends StatelessWidget {
             ),
             boxShadow: [
               BoxShadow(
-                color: controller.gradientColors[0].withOpacity(0.3),
+                color: controller.gradientColors[0].withValues(alpha: 0.3),
                 blurRadius: 20,
                 spreadRadius: 0,
                 offset: const Offset(0, 8),
@@ -44,7 +44,7 @@ class AddSubscriptionHeader extends StatelessWidget {
               Container(
                 padding: const EdgeInsets.all(16),
                 decoration: BoxDecoration(
-                  color: Colors.white.withOpacity(0.2),
+                  color: Colors.white.withValues(alpha: 0.2),
                   borderRadius: BorderRadius.circular(16),
                 ),
                 child: const Icon(