refactor: 替换硬编码的AppTypography为基于context的动态获取

1. 批量修改所有直接调用AppTypography静态方法的地方，改为使用AppTypography.of(context)获取主题文本样式，适配不同主题上下文
2. 新增channelOrder存储键，支持频道排序持久化
3. 修复笔记删除全部功能未重置total字段的bug
4. 调整build.yaml配置，扩展freezed和json_serializable的生成范围
5. 优化底部弹窗默认样式，使用主题色替代硬编码颜色
6. 调整主题设置中的卡片样式默认文案

lib/core/layout/app_shell.dart

@@ -1,4 +1,4 @@
-// ============================================================
+// ============================================================
 // 闲言APP — 应用布局壳
 // 创建时间: 2026-04-20
 // 更新时间: 2026-05-18
@@ -80,10 +80,10 @@ class AppShell extends ConsumerWidget {
                 label: '',
                 icon: badges.Badge(
                   showBadge: unreadCount > 0,
-                  badgeContent: const Text(
+                  badgeContent: Text(
                     '',
                     style: TextStyle(
-                      color: Colors.white,
+                      color: ext.textOnAccent,
                       fontSize: 9,
                       fontWeight: FontWeight.bold,
                     ),
@@ -97,10 +97,10 @@ class AppShell extends ConsumerWidget {
                 ),
                 activeIcon: badges.Badge(
                   showBadge: unreadCount > 0,
-                  badgeContent: const Text(
+                  badgeContent: Text(
                     '',
                     style: TextStyle(
-                      color: Colors.white,
+                      color: ext.textOnAccent,
                       fontSize: 9,
                       fontWeight: FontWeight.bold,
                     ),
@@ -124,17 +124,17 @@ class AppShell extends ConsumerWidget {
             selectedIndex: currentIndex,
             onTabSelected: (index) => _onTabTap(context, index),
             quality: GlassQuality.premium,
-            selectedIconColor: ext.isDark ? Colors.white : ext.accent,
+            selectedIconColor: ext.isDark ? ext.textInverse : ext.accent,
             unselectedIconColor: ext.isDark
-                ? Colors.white38
+                ? ext.textInverse.withValues(alpha: 0.38)
                 : const Color(0xFFAEAEB2),
             barHeight: 68,
             barBorderRadius: 34,
             horizontalPadding: 16,
             verticalPadding: 16,
             indicatorColor: ext.isDark
-                ? Colors.white.withValues(alpha: 0.08)
-                : Colors.black.withValues(alpha: 0.04),
+                ? ext.textInverse.withValues(alpha: 0.08)
+                : ext.overlaySubtle,
             indicatorSettings: LiquidGlassSettings(
               thickness: 40,
               blur: 25,
@@ -205,7 +205,10 @@ class AppShell extends ConsumerWidget {
           label: t.navDiscover,
           badgeCount: unreadCount,
         ),
-        GlassBottomNavBarItem(spriteType: TabSpriteType.profile, label: t.navProfile),
+        GlassBottomNavBarItem(
+          spriteType: TabSpriteType.profile,
+          label: t.navProfile,
+        ),
       ],
       selectedIndex: currentIndex,
       onTabSelected: (index) => _onTabTap(context, index),