feat(frontend): add four-quadrant kanban task management system

- Add KanbanPanel component with four-quadrant task layout
- Add KanbanDetail component for task configuration modal
- Add "待办" (Todo) module to sidebar collapsed icon rail
- Click TODAY'S STATUS card or sidebar icon to open kanban drawer
- Click quadrant check icon to open detail modal with Teleport to body
- Apply blur effect to sidebar and chat area when detail modal is open
- Import ListTodo icon from lucide-vue-next
- Update sidebar labels to English for consistency

frontend/src/pages/chat/composables/useSidebarPlan.ts

@@ -1,5 +1,5 @@
 import { computed, onMounted, ref, watch } from 'vue'
-import { CornerDownLeft, Database, Sparkles, Sun } from 'lucide-vue-next'
+import { CornerDownLeft, Database, Sparkles, Sun, ListTodo } from 'lucide-vue-next'
 import { scheduleCenterApi, type ScheduleCenterDateResponse, type ScheduleCenterDaySummary } from '@/api/scheduleCenter'
 
 export interface SidebarFocusItem {
@@ -13,6 +13,7 @@ export const sidebarCollapsedModules = [
   { id: 'calendar', label: '日历', icon: Sun },
   { id: 'status', label: '计划', icon: Database },
   { id: 'focus', label: '重点', icon: Sparkles },
+  { id: 'kanban', label: '待办', icon: ListTodo },
   { id: 'review', label: '复盘', icon: CornerDownLeft },
 ]
 
@@ -111,10 +112,10 @@ export function useSidebarPlan(clientTimeRef: { value: Date }, loadDailyDigestFn
   ))
 
   const sidebarStatusBreakdown = computed(() => [
-    { key: 'done', label: '已完成', value: todayPlanCounters.value.done, tone: 'done' },
-    { key: 'doing', label: '进行中', value: todayPlanCounters.value.doing, tone: 'doing' },
-    { key: 'pending', label: '未开始', value: todayPlanCounters.value.pending, tone: 'pending' },
-    { key: 'total', label: '今日合计', value: todayPlanCounters.value.total, tone: 'total' },
+    { key: 'done', label: 'Completed', value: todayPlanCounters.value.done, tone: 'done' },
+    { key: 'doing', label: 'In Progress', value: todayPlanCounters.value.doing, tone: 'doing' },
+    { key: 'pending', label: 'Pending', value: todayPlanCounters.value.pending, tone: 'pending' },
+    { key: 'total', label: 'Total', value: todayPlanCounters.value.total, tone: 'total' },
   ])
 
   // 模拟数据 - 用于测试滑动条