결재 템플릿 단계 적용 구현

- ApprovalTemplate 엔티티·DTO·원격 리포지토리 추가
- ApprovalController에 템플릿 로딩/적용 상태와 assignSteps 호출 연동
- ApprovalPage 단계 탭에 템플릿 선택 UI 및 적용 확인 다이얼로그 구현
- 템플릿 적용 단위 테스트와 IMPLEMENTATION_TASKS 현황 갱신

lib/widgets/components/coming_soon_card.dart

@@ -0,0 +1,49 @@
+import 'package:flutter/widgets.dart';
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+/// 구축 예정인 화면에 안내 메시지를 제공하는 카드 위젯.
+class ComingSoonCard extends StatelessWidget {
+  const ComingSoonCard({
+    super.key,
+    required this.title,
+    required this.description,
+    this.items = const <String>[],
+  });
+
+  final String title;
+  final String description;
+  final List<String> items;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = ShadTheme.of(context);
+
+    return ShadCard(
+      child: Padding(
+        padding: const EdgeInsets.all(24),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(title, style: theme.textTheme.h3),
+            const SizedBox(height: 12),
+            Text(description, style: theme.textTheme.p),
+            if (items.isNotEmpty) ...[
+              const SizedBox(height: 16),
+              for (final item in items)
+                Padding(
+                  padding: const EdgeInsets.only(top: 8),
+                  child: Row(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      const Text('• '),
+                      Expanded(child: Text(item, style: theme.textTheme.p)),
+                    ],
+                  ),
+                ),
+            ],
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/widgets/components/empty_state.dart

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+import 'package:flutter/material.dart';
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+class EmptyState extends StatelessWidget {
+  const EmptyState({super.key, required this.message, this.icon});
+
+  final String message;
+  final IconData? icon;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = ShadTheme.of(context);
+    return Center(
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          if (icon != null)
+            Icon(icon, size: 48, color: theme.colorScheme.mutedForeground),
+          if (icon != null) const SizedBox(height: 16),
+          Text(message, style: theme.textTheme.muted),
+        ],
+      ),
+    );
+  }
+}

lib/widgets/components/filter_bar.dart

@@ -0,0 +1,25 @@
+import 'package:flutter/material.dart';
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+/// 검색/필터 영역을 위한 공통 래퍼.
+class FilterBar extends StatelessWidget {
+  const FilterBar({super.key, required this.children});
+
+  final List<Widget> children;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = ShadTheme.of(context);
+    return ShadCard(
+      title: Text('검색 및 필터', style: theme.textTheme.h3),
+      child: Align(
+        alignment: Alignment.centerLeft,
+        child: Wrap(
+          spacing: 16,
+          runSpacing: 16,
+          children: children,
+        ),
+      ),
+    );
+  }
+}

lib/widgets/components/page_header.dart

@@ -0,0 +1,58 @@
+import 'package:flutter/material.dart';
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+/// 페이지 상단 타이틀/설명/액션을 일관되게 출력하는 헤더.
+class PageHeader extends StatelessWidget {
+  const PageHeader({
+    super.key,
+    required this.title,
+    this.subtitle,
+    this.leading,
+    this.actions,
+    this.trailing,
+  });
+
+  final String title;
+  final String? subtitle;
+  final Widget? leading;
+  final List<Widget>? actions;
+  final Widget? trailing;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = ShadTheme.of(context);
+
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        if (leading != null) ...[
+          leading!,
+          const SizedBox(width: 16),
+        ],
+        Expanded(
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              Text(title, style: theme.textTheme.h2),
+              if (subtitle != null) ...[
+                const SizedBox(height: 6),
+                Text(subtitle!, style: theme.textTheme.muted),
+              ],
+            ],
+          ),
+        ),
+        if (actions != null && actions!.isNotEmpty) ...[
+          Wrap(
+            spacing: 12,
+            runSpacing: 12,
+            children: actions!,
+          ),
+        ],
+        if (trailing != null) ...[
+          const SizedBox(width: 16),
+          trailing!,
+        ],
+      ],
+    );
+  }
+}

lib/widgets/components/responsive.dart

@@ -0,0 +1,6 @@
+const double desktopBreakpoint = 1200;
+const double tabletBreakpoint = 960;
+
+bool isDesktop(double width) => width >= desktopBreakpoint;
+bool isTablet(double width) => width >= tabletBreakpoint && width < desktopBreakpoint;
+bool isMobile(double width) => width < tabletBreakpoint;

lib/widgets/components/superport_dialog.dart

@@ -0,0 +1,40 @@
+import 'package:flutter/material.dart';
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+/// 공통 모달 다이얼로그.
+Future<T?> showSuperportDialog<T>({
+  required BuildContext context,
+  required String title,
+  String? description,
+  required Widget body,
+  List<Widget>? actions,
+  bool barrierDismissible = true,
+}) {
+  return showDialog<T>(
+    context: context,
+    barrierDismissible: barrierDismissible,
+    builder: (dialogContext) {
+      final theme = ShadTheme.of(dialogContext);
+      return Dialog(
+        insetPadding: const EdgeInsets.all(24),
+        clipBehavior: Clip.antiAlias,
+        child: ShadCard(
+          title: Text(title, style: theme.textTheme.h3),
+          description: description == null
+              ? null
+              : Text(description, style: theme.textTheme.muted),
+          footer: Row(
+            mainAxisAlignment: MainAxisAlignment.end,
+            children: actions ?? <Widget>[
+              ShadButton.ghost(
+                onPressed: () => Navigator.of(dialogContext).pop(),
+                child: const Text('닫기'),
+              ),
+            ],
+          ),
+          child: body,
+        ),
+      );
+    },
+  );
+}

lib/widgets/components/superport_table.dart

@@ -0,0 +1,58 @@
+import 'package:flutter/material.dart';
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+/// ShadTable.list를 감싼 공통 테이블 래퍼.
+class SuperportTable extends StatelessWidget {
+  const SuperportTable({
+    super.key,
+    required this.columns,
+    required this.rows,
+    this.columnSpanExtent,
+    this.rowHeight = 56,
+    this.onRowTap,
+    this.emptyLabel = '데이터가 없습니다.',
+  });
+
+  final List<Widget> columns;
+  final List<List<Widget>> rows;
+  final TableSpanExtent? Function(int index)? columnSpanExtent;
+  final double rowHeight;
+  final void Function(int index)? onRowTap;
+  final String emptyLabel;
+
+  @override
+  Widget build(BuildContext context) {
+    if (rows.isEmpty) {
+      final theme = ShadTheme.of(context);
+      return Padding(
+        padding: const EdgeInsets.all(32),
+        child: Center(
+          child: Text(emptyLabel, style: theme.textTheme.muted),
+        ),
+      );
+    }
+
+    final tableRows = [
+      for (final row in rows)
+        row
+            .map(
+              (cell) => cell is ShadTableCell ? cell : ShadTableCell(child: cell),
+            )
+            .toList(),
+    ];
+
+    return ShadTable.list(
+      header: columns
+          .map(
+            (cell) => cell is ShadTableCell
+                ? cell
+                : ShadTableCell.header(child: cell),
+          )
+          .toList(),
+      columnSpanExtent: columnSpanExtent,
+      rowSpanExtent: (_) => FixedTableSpanExtent(rowHeight),
+      onRowTap: onRowTap,
+      children: tableRows,
+    );
+  }
+}