fix(app/schedule): 날짜 스크롤 가운데 정렬 및 divider 너비 수정

- 날짜 선택 시 ListView padding을 고려하여 정확히 가운데로 스크롤
- 일정 카드의 멤버 divider가 콘텐츠 영역 전체 너비를 채우도록 수정

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/lib/views/schedule/schedule_view.dart

@@ -226,8 +226,10 @@ class _ScheduleViewState extends ConsumerState<ScheduleView>
 
     final dayIndex = selectedDate.day - 1;
     const itemWidth = 52.0; // 44 + 8 (gap)
+    const horizontalPadding = 8.0; // ListView padding
     final targetOffset =
-        (dayIndex * itemWidth) -
+        (dayIndex * itemWidth) +
+        horizontalPadding -
         (MediaQuery.of(context).size.width / 2) +
         (itemWidth / 2);
     _dateScrollController.animateTo(

app/lib/views/schedule/widgets/schedule_card.dart

@@ -225,24 +225,23 @@ class ScheduleCard extends StatelessWidget {
             // 멤버
             if (memberList.isNotEmpty) ...[
               const SizedBox(height: 12),
+              // divider (전체 너비)
               Container(
-                padding: const EdgeInsets.only(top: 12),
-                decoration: const BoxDecoration(
-                  border: Border(
-                    top: BorderSide(color: AppColors.divider, width: 1),
-                  ),
-                ),
-                child: Wrap(
-                  spacing: 6,
-                  runSpacing: 6,
-                  children: memberList.length >= 5
-                      ? [
-                          const MemberChip(name: '프로미스나인'),
-                        ]
-                      : memberList
-                          .map((name) => MemberChip(name: name))
-                          .toList(),
-                ),
+                width: double.infinity,
+                height: 1,
+                color: AppColors.divider,
+              ),
+              const SizedBox(height: 12),
+              Wrap(
+                spacing: 6,
+                runSpacing: 6,
+                children: memberList.length >= 5
+                    ? [
+                        const MemberChip(name: '프로미스나인'),
+                      ]
+                    : memberList
+                        .map((name) => MemberChip(name: name))
+                        .toList(),
               ),
             ],
           ],