feat(pagination): 공통 컨트롤 도입과 사용자 관리 가이드 추가

- 테이블 푸터에서 SuperportPaginationControls를 사용하도록 각 관리 페이지 페이지네이션 로직을 정리

- SuperportPaginationControls 위젯을 추가하고 SuperportTable 푸터를 개선해 페이지 사이즈 선택과 이동 버튼을 분리

- 사용자 등록·계정 관리 요구사항을 문서화한 doc/user_setting.md를 작성하고 AGENTS.md 코멘트 규칙을 업데이트

- flutter analyze를 수행해 빌드 경고가 없음을 확인

lib/widgets/components/superport_pagination_controls.dart

@@ -0,0 +1,98 @@
+import 'package:flutter/material.dart';
+import 'package:lucide_icons_flutter/lucide_icons.dart' as lucide;
+import 'package:shadcn_ui/shadcn_ui.dart';
+
+/// 페이지 이동용 <<, <, >, >> 버튼을 공통 스타일로 제공하는 위젯.
+class SuperportPaginationControls extends StatelessWidget {
+  const SuperportPaginationControls({
+    super.key,
+    required this.currentPage,
+    required this.totalPages,
+    this.onPageSelected,
+    this.isBusy = false,
+    this.size = ShadButtonSize.sm,
+    this.spacing = 8,
+    this.mainAxisSize = MainAxisSize.min,
+  });
+
+  /// 현재 선택된 페이지 번호(1-base).
+  final int currentPage;
+
+  /// 전체 페이지 수.
+  final int totalPages;
+
+  /// 페이지 변경 콜백. `null`이면 모든 버튼을 비활성화한다.
+  final void Function(int page)? onPageSelected;
+
+  /// 비동기 작업 중 여부. `true`면 버튼이 비활성화된다.
+  final bool isBusy;
+
+  /// 버튼 크기 옵션.
+  final ShadButtonSize size;
+
+  /// 버튼 간 간격.
+  final double spacing;
+
+  /// 내부 Row의 MainAxisSize.
+  final MainAxisSize mainAxisSize;
+
+  @override
+  Widget build(BuildContext context) {
+    final int safeTotal = totalPages <= 0 ? 1 : totalPages;
+    final int safeCurrent = currentPage < 1
+        ? 1
+        : (currentPage > safeTotal ? safeTotal : currentPage);
+    final bool canInteract = onPageSelected != null && !isBusy;
+    final bool canGoPrev = canInteract && safeCurrent > 1;
+    final bool canGoNext = canInteract && safeCurrent < safeTotal;
+
+    return Row(
+      mainAxisSize: mainAxisSize,
+      children: _withSpacing([
+        _buildButton(
+          icon: lucide.LucideIcons.chevronsLeft,
+          enabled: canGoPrev,
+          onTap: () => onPageSelected?.call(1),
+        ),
+        _buildButton(
+          icon: lucide.LucideIcons.chevronLeft,
+          enabled: canGoPrev,
+          onTap: () => onPageSelected?.call(safeCurrent - 1),
+        ),
+        _buildButton(
+          icon: lucide.LucideIcons.chevronRight,
+          enabled: canGoNext,
+          onTap: () => onPageSelected?.call(safeCurrent + 1),
+        ),
+        _buildButton(
+          icon: lucide.LucideIcons.chevronsRight,
+          enabled: canGoNext,
+          onTap: () => onPageSelected?.call(safeTotal),
+        ),
+      ]),
+    );
+  }
+
+  List<Widget> _withSpacing(List<Widget> children) {
+    final result = <Widget>[];
+    for (var i = 0; i < children.length; i++) {
+      if (i > 0) {
+        result.add(SizedBox(width: spacing));
+      }
+      result.add(children[i]);
+    }
+    return result;
+  }
+
+  Widget _buildButton({
+    required IconData icon,
+    required bool enabled,
+    required VoidCallback onTap,
+  }) {
+    return ShadButton.ghost(
+      size: size,
+      onPressed: enabled ? onTap : null,
+      child: Icon(icon, size: 16),
+    );
+  }
+}

lib/widgets/components/superport_table.dart

@@ -3,6 +3,7 @@ import 'dart:math' as math;
 import 'package:flutter/material.dart';
 import 'package:lucide_icons_flutter/lucide_icons.dart' as lucide;
 import 'package:shadcn_ui/shadcn_ui.dart';
+import 'package:superport_v2/widgets/components/superport_pagination_controls.dart';
 
 /// 테이블 정렬 상태 정보를 보관하는 모델.
 class SuperportTableSortState {
@@ -276,15 +277,14 @@ class _PaginationFooter extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final theme = ShadTheme.of(context);
-    final int totalPages =
-        pagination.totalPages <= 0 ? 1 : pagination.totalPages;
+    final int totalPages = pagination.totalPages <= 0
+        ? 1
+        : pagination.totalPages;
     final int currentPage = pagination.currentPage < 1
         ? 1
         : (pagination.currentPage > totalPages
-            ? totalPages
-            : pagination.currentPage);
-    final canGoPrev = currentPage > 1 && !isLoading;
-    final canGoNext = currentPage < totalPages && !isLoading;
+              ? totalPages
+              : pagination.currentPage);
 
     return Row(
       mainAxisAlignment: MainAxisAlignment.spaceBetween,
@@ -316,33 +316,11 @@ class _PaginationFooter extends StatelessWidget {
               style: theme.textTheme.small,
             ),
             const SizedBox(width: 12),
-            ShadButton.ghost(
-              size: ShadButtonSize.sm,
-              onPressed: canGoPrev ? () => onPageChange?.call(1) : null,
-              child: const Icon(lucide.LucideIcons.chevronsLeft, size: 16),
-            ),
-            const SizedBox(width: 8),
-            ShadButton.ghost(
-              size: ShadButtonSize.sm,
-              onPressed: canGoPrev
-                  ? () => onPageChange?.call(currentPage - 1)
-                  : null,
-              child: const Icon(lucide.LucideIcons.chevronLeft, size: 16),
-            ),
-            const SizedBox(width: 8),
-            ShadButton.ghost(
-              size: ShadButtonSize.sm,
-              onPressed: canGoNext
-                  ? () => onPageChange?.call(currentPage + 1)
-                  : null,
-              child: const Icon(lucide.LucideIcons.chevronRight, size: 16),
-            ),
-            const SizedBox(width: 8),
-            ShadButton.ghost(
-              size: ShadButtonSize.sm,
-              onPressed:
-                  canGoNext ? () => onPageChange?.call(totalPages) : null,
-              child: const Icon(lucide.LucideIcons.chevronsRight, size: 16),
+            SuperportPaginationControls(
+              currentPage: currentPage,
+              totalPages: totalPages,
+              onPageSelected: onPageChange,
+              isBusy: isLoading,
             ),
           ],
         ),