fix: patch P0 security vulnerabilities and critical UX issues across 6 modules

Security: Add admin/layout.tsx auth guard; Add requirePermission() to 12 admin pages

Dashboard: Fix StudentStatsGrid rendering; Fix teacher greeting; Add loading/error boundaries; Fix col-span; Add metadata

Announcements: Fix audience filtering; Add user detail page; Trigger notifications on publish; Pass classes data; Add loading.tsx

Messages: Implement soft delete; Add unread badge with polling; Add notification dropdown polling; Add keyword search; Add quiet hours DND

Management: Add loading/error for 9 admin routes; Fix admin-classes-view to use Select for school/grade

Profile/Settings: Add loading/error; Fix parent role routing; Create ParentSettingsView; Integrate AiProviderSettingsCard; Add Tab URL persistence; Add logout confirm; Add avatar; Fix Progress arbitrary class

Schema: Add senderDeletedAt/receiverDeletedAt to messages; Add quietHours to notificationPreferences; Add uniqueIndex import

Docs: Update architecture docs 004/005

src/modules/settings/components/notification-preferences-form.tsx

@@ -3,14 +3,16 @@
 import * as React from "react"
 import { useActionState } from "react"
 import { useFormStatus } from "react-dom"
-import { Loader2, Save, Bell, Mail, MessageSquare, Megaphone, GraduationCap, BookOpen, CalendarCheck } from "lucide-react"
+import { Loader2, Save, Bell, Mail, MessageSquare, Megaphone, GraduationCap, BookOpen, CalendarCheck, Moon } from "lucide-react"
 import { toast } from "sonner"
 
 import { Button } from "@/shared/components/ui/button"
 import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/shared/components/ui/card"
+import { Input } from "@/shared/components/ui/input"
 import { Switch } from "@/shared/components/ui/switch"
 import { Label } from "@/shared/components/ui/label"
 import { Separator } from "@/shared/components/ui/separator"
+import { cn } from "@/shared/lib/utils"
 import { updateNotificationPreferencesAction } from "@/modules/messaging/actions"
 import type { NotificationPreferences } from "@/modules/notifications/types"
 
@@ -131,6 +133,11 @@ export function NotificationPreferencesForm({ preferences }: NotificationPrefere
     messageNotifications: preferences.messageNotifications,
     attendanceNotifications: preferences.attendanceNotifications,
   })
+  const [quietHours, setQuietHours] = React.useState({
+    quietHoursEnabled: preferences.quietHoursEnabled,
+    quietHoursStart: preferences.quietHoursStart ?? "",
+    quietHoursEnd: preferences.quietHoursEnd ?? "",
+  })
 
   React.useEffect(() => {
     if (state?.success) {
@@ -148,6 +155,10 @@ export function NotificationPreferencesForm({ preferences }: NotificationPrefere
     setCategories((prev) => ({ ...prev, [key]: !prev[key] }))
   }
 
+  const toggleQuietHours = () => {
+    setQuietHours((prev) => ({ ...prev, quietHoursEnabled: !prev.quietHoursEnabled }))
+  }
+
   return (
     <Card>
       <CardHeader>
@@ -250,6 +261,80 @@ export function NotificationPreferencesForm({ preferences }: NotificationPrefere
               )
             })}
           </div>
+
+          <Separator />
+
+          {/* 免打扰时段 */}
+          <div className="space-y-4">
+            <div>
+              <h4 className="text-sm font-medium">Quiet Hours</h4>
+              <p className="text-xs text-muted-foreground">
+                Suppress non-urgent notifications during a specified time period each day.
+              </p>
+            </div>
+            <div className="flex items-center justify-between gap-4">
+              <div className="flex items-start gap-3">
+                <div className="flex h-9 w-9 items-center justify-center rounded-md bg-muted">
+                  <Moon className="h-4 w-4 text-muted-foreground" />
+                </div>
+                <div className="space-y-0.5">
+                  <Label htmlFor="quietHoursEnabled" className="text-sm font-medium cursor-pointer">
+                    Enable Quiet Hours
+                  </Label>
+                  <p className="text-xs text-muted-foreground">
+                    When enabled, only urgent notifications will be delivered during the specified hours.
+                  </p>
+                </div>
+              </div>
+              <div className="flex items-center gap-2">
+                <input
+                  type="checkbox"
+                  name="quietHoursEnabled"
+                  checked={quietHours.quietHoursEnabled}
+                  onChange={toggleQuietHours}
+                  className="sr-only"
+                  tabIndex={-1}
+                />
+                <Switch
+                  id="quietHoursEnabled"
+                  checked={quietHours.quietHoursEnabled}
+                  onCheckedChange={toggleQuietHours}
+                  aria-label="Enable Quiet Hours"
+                />
+              </div>
+            </div>
+            <div className={cn(
+              "grid gap-4 sm:grid-cols-2 transition-opacity",
+              !quietHours.quietHoursEnabled && "pointer-events-none opacity-50"
+            )}>
+              <div className="space-y-2">
+                <Label htmlFor="quietHoursStart" className="text-xs font-medium">
+                  Start Time
+                </Label>
+                <Input
+                  id="quietHoursStart"
+                  name="quietHoursStart"
+                  type="time"
+                  value={quietHours.quietHoursStart}
+                  onChange={(e) => setQuietHours((prev) => ({ ...prev, quietHoursStart: e.target.value }))}
+                  disabled={!quietHours.quietHoursEnabled}
+                />
+              </div>
+              <div className="space-y-2">
+                <Label htmlFor="quietHoursEnd" className="text-xs font-medium">
+                  End Time
+                </Label>
+                <Input
+                  id="quietHoursEnd"
+                  name="quietHoursEnd"
+                  type="time"
+                  value={quietHours.quietHoursEnd}
+                  onChange={(e) => setQuietHours((prev) => ({ ...prev, quietHoursEnd: e.target.value }))}
+                  disabled={!quietHours.quietHoursEnabled}
+                />
+              </div>
+            </div>
+          </div>
         </CardContent>
         <CardFooter className="flex justify-end border-t px-6 py-4">
           <SubmitButton />