senior's post-demo changes: parent report in the student's own account, Jalali birth date, invoices, math-only tutor, priced quotas

- remove the family app from the root (separate parent accounts, invite codes, parental
  settings); progress.0006 drops its tables, permissions and migration history, and
  Profile.parent_phone, the two family notification types and ?userId= on
  /api/progress/nodes go with it
- GET /api/user/weekly-report: last 7 days next to the 7 before (estimated minutes,
  questions, accuracy, islands, tutor questions) for the "parent report" page
- profile birthDate in Jalali (accounts/jalali.py), ages 5-99, birthYear derived from it
- GET /api/payment/invoices; orders now snapshot list price and plan title
- tutor answers only math: server pre-filter, scope rule in the prompt (tutor-v11),
  refusal marker replaced with fixed text; self-harm gets a help line instead
- streamed answers now record token usage (it was always 0)
- daily tutor quota: AI_DAILY_QUOTA_FREE (default 3) vs Plan.ai_daily_quota
- delete_users management command for wiping test accounts across every app
- docs/ai-cost-and-guardrails.md: measured cost per question and guardrail results

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

progress/views.py

@@ -32,6 +32,7 @@ from .serializers import (
     StreakCalendarResponseSerializer,
     UserHeartsResponseSerializer,
     UserSummaryResponseSerializer,
+    WeeklyReportResponseSerializer,
 )
 
 
@@ -100,6 +101,26 @@ class StreakCalendarView(APIView):
         return Response(StreakCalendarResponseSerializer(data).data)
 
 
+class WeeklyReportView(APIView):
+    """
+    GET /api/user/weekly-report — گزارشِ ۷ روزِ اخیرِ خودِ کاربر در کنارِ ۷ روزِ قبلش.
+
+    فرانت آن را با عنوانِ «گزارشِ والدین» نشان می‌دهد؛ والد همین را در حسابِ خودِ
+    دانش‌آموز می‌بیند و حسابِ جدا ندارد. فقط دیتای خودِ درخواست‌دهنده را برمی‌گرداند.
+    محاسبه و این‌که `minutes` تخمینی است: `progress/report.py`.
+    """
+
+    permission_classes = [IsAuthenticated]
+    throttle_scope = 'read'
+    throttle_classes = [GuestAwareReadThrottle]
+
+    @extend_schema(responses=WeeklyReportResponseSerializer, tags=['Progress & Gamification (progress)'])
+    def get(self, request):
+        from .report import weekly_report
+
+        return Response(WeeklyReportResponseSerializer(weekly_report(request.user.id)).data)
+
+
 # کوتاه تا XPی تازه زود دیده شود، بلند تا هزار کاربرِ هم‌زمان هر بار جدول را
 # از نو حساب نکنند.
 LEADERBOARD_CACHE_TTL = 60