feat(client): 列表屏搜索前置/显示字段记忆/移动端表格切换与工具栏瘦身/退出登录归位

- 库存查询搜索框移到工具栏最前（桌面）/独占首行（移动端）
- 修复入库/出库/财务「显示字段」失效：移除 minWidth 运行时强制隐藏，
  用户勾选权威、minWidth 仅作首次默认；新增 ColumnPrefs 持久化记忆（四屏独立）
- 移动端库存支持表格/卡片列表切换
- 移动端三个列表屏工具栏改 Wrap 紧凑布局、导出/显示字段图标化
- 退出登录统一到左侧导航：删系统设置内与桌面右上角下拉，桌面左侧栏底部新增

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/lib/screens/shell/app_shell.dart

@@ -289,16 +289,6 @@ class _AppShellState extends ConsumerState<AppShell> {
                           label: '个人设置',
                         ),
                       ),
-                      const PopupMenuDivider(height: 1),
-                      const PopupMenuItem<String>(
-                        value: 'logout',
-                        padding: EdgeInsets.zero,
-                        child: _HoverMenuItem(
-                          icon: Icons.logout_outlined,
-                          label: '退出登录',
-                          danger: true,
-                        ),
-                      ),
                     ],
                   ),
                   const SizedBox(width: 8),
@@ -334,6 +324,48 @@ class _AppShellState extends ConsumerState<AppShell> {
                             }).toList(),
                           ),
                         ),
+                        // 退出登录（侧栏底部常驻；统一为左侧导航唯一退出入口）
+                        const Divider(height: 1, color: Colors.white24),
+                        SizedBox(
+                          height: 48,
+                          child: Material(
+                            color: Colors.transparent,
+                            child: InkWell(
+                              onTap: () {
+                                ref
+                                    .read(authStateProvider.notifier)
+                                    .logout();
+                                context.go('/login');
+                              },
+                              hoverColor: Colors.white.withAlpha(13),
+                              splashColor: Colors.white.withAlpha(26),
+                              child: Row(
+                                children: [
+                                  SizedBox(width: _sidebarExpanded ? 16 : 3),
+                                  Expanded(
+                                    child: Row(
+                                      mainAxisAlignment: _sidebarExpanded
+                                          ? MainAxisAlignment.start
+                                          : MainAxisAlignment.center,
+                                      children: [
+                                        const Icon(Icons.logout,
+                                            color: Colors.white60, size: 20),
+                                        if (_sidebarExpanded) ...[
+                                          const SizedBox(width: 12),
+                                          const Text('退出登录',
+                                              style: TextStyle(
+                                                  color: Colors.white70,
+                                                  fontSize: 14)),
+                                        ],
+                                      ],
+                                    ),
+                                  ),
+                                ],
+                              ),
+                            ),
+                          ),
+                        ),
+                        const SizedBox(height: 8),
                       ],
                     ),
                   ),
@@ -930,12 +962,10 @@ class _InfoRow extends StatelessWidget {
 class _HoverMenuItem extends StatefulWidget {
   final IconData icon;
   final String label;
-  final bool danger;
 
   const _HoverMenuItem({
     required this.icon,
     required this.label,
-    this.danger = false,
   });
 
   @override
@@ -947,12 +977,8 @@ class _HoverMenuItemState extends State<_HoverMenuItem> {
 
   @override
   Widget build(BuildContext context) {
-    final color = widget.danger
-        ? const Color(0xFFE53935)
-        : const Color(0xFF333333);
-    final hoverBg = widget.danger
-        ? const Color(0xFFFFF0F0)
-        : const Color(0xFFF0F4FF);
+    const color = Color(0xFF333333);
+    const hoverBg = Color(0xFFF0F4FF);
 
     return MouseRegion(
       onEnter: (_) => setState(() => _hovered = true),