feat: 폼 필드 컴포넌트 분리 및 구독 카드 인터랙션 개선

- billing_cycle_selector, category_selector, currency_selector 컴포넌트 분리
- 구독 카드 클릭 이슈 해결을 위한 리팩토링
- SMS 스캔 화면 UI/UX 개선 및 기능 강화
- 상세 화면 컨트롤러 로직 개선
- 알림 서비스 및 구독 URL 매칭 기능 추가
- CLAUDE.md 프로젝트 가이드라인 대폭 확장
- 전반적인 코드 구조 개선 및 타입 안정성 강화

🤖 Generated with [Claude Code](https://claude.ai/code)

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

lib/widgets/detail/detail_event_section.dart

@@ -1,5 +1,7 @@
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 import '../../controllers/detail_screen_controller.dart';
+import '../../theme/app_colors.dart';
 import '../common/form_fields/currency_input_field.dart';
 import '../common/form_fields/date_picker_field.dart';
 
@@ -19,9 +21,11 @@ class DetailEventSection extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final baseColor = controller.getCardColor();
+    return Consumer<DetailScreenController>(
+      builder: (context, controller, child) {
+        final baseColor = controller.getCardColor();
 
-    return FadeTransition(
+        return FadeTransition(
       opacity: fadeAnimation,
       child: SlideTransition(
         position: Tween<Offset>(
@@ -31,11 +35,21 @@ class DetailEventSection extends StatelessWidget {
           parent: controller.animationController!,
           curve: const Interval(0.4, 1.0, curve: Curves.easeOutCubic),
         )),
-        child: Card(
-          elevation: 1,
-          shadowColor: Colors.black12,
-          shape: RoundedRectangleBorder(
+        child: Container(
+          decoration: BoxDecoration(
+            color: AppColors.glassCard,
             borderRadius: BorderRadius.circular(20),
+            border: Border.all(
+              color: AppColors.glassBorder.withValues(alpha: 0.1),
+              width: 1,
+            ),
+            boxShadow: [
+              BoxShadow(
+                color: AppColors.shadowBlack,
+                blurRadius: 10,
+                offset: const Offset(0, 4),
+              ),
+            ],
           ),
           child: Padding(
             padding: const EdgeInsets.all(24),
@@ -66,6 +80,7 @@ class DetailEventSection extends StatelessWidget {
                           style: TextStyle(
                             fontSize: 18,
                             fontWeight: FontWeight.w700,
+                            color: AppColors.darkNavy,
                           ),
                         ),
                       ],
@@ -93,14 +108,18 @@ class DetailEventSection extends StatelessWidget {
                   Container(
                     padding: const EdgeInsets.all(12),
                     decoration: BoxDecoration(
-                      color: Colors.blue.withValues(alpha: 0.1),
+                      color: AppColors.infoColor.withValues(alpha: 0.08),
                       borderRadius: BorderRadius.circular(12),
+                      border: Border.all(
+                        color: AppColors.infoColor.withValues(alpha: 0.3),
+                        width: 1,
+                      ),
                     ),
                     child: Row(
                       children: [
                         Icon(
                           Icons.info_outline_rounded,
-                          color: Colors.blue[700],
+                          color: AppColors.infoColor,
                           size: 20,
                         ),
                         const SizedBox(width: 8),
@@ -109,7 +128,8 @@ class DetailEventSection extends StatelessWidget {
                             '할인 또는 프로모션 가격을 설정하세요',
                             style: TextStyle(
                               fontSize: 14,
-                              color: Colors.blue[700],
+                              color: AppColors.darkNavy,
+                              fontWeight: FontWeight.w500,
                             ),
                           ),
                         ),
@@ -123,6 +143,10 @@ class DetailEventSection extends StatelessWidget {
                     endDate: controller.eventEndDate,
                     onStartDateSelected: (date) {
                       controller.eventStartDate = date;
+                      // 시작일 설정 시 종료일이 없으면 자동으로 1달 후로 설정
+                      if (date != null && controller.eventEndDate == null) {
+                        controller.eventEndDate = date.add(const Duration(days: 30));
+                      }
                     },
                     onEndDateSelected: (date) {
                       controller.eventEndDate = date;
@@ -138,6 +162,18 @@ class DetailEventSection extends StatelessWidget {
                     currency: controller.currency,
                     label: '이벤트 가격',
                     hintText: '할인된 가격을 입력하세요',
+                    validator: controller.isEventActive
+                        ? (value) {
+                            if (value == null || value.isEmpty) {
+                              return '이벤트 가격을 입력해주세요';
+                            }
+                            final price = double.tryParse(value.replaceAll(',', ''));
+                            if (price == null || price <= 0) {
+                              return '올바른 가격을 입력해주세요';
+                            }
+                            return null;
+                          }
+                        : null,
                   ),
                   const SizedBox(height: 16),
                   // 할인율 표시
@@ -156,6 +192,8 @@ class DetailEventSection extends StatelessWidget {
         ),
       ),
     );
+      },
+    );
   }
 }
 
@@ -209,7 +247,7 @@ class _DiscountBadge extends StatelessWidget {
                 ? '₩${discountAmount.toInt().toString()}원 절약'
                 : '\$${discountAmount.toStringAsFixed(2)} 절약',
             style: TextStyle(
-              color: Colors.green[700],
+              color: const Color(0xFF15803D),
               fontSize: 14,
               fontWeight: FontWeight.w500,
             ),