Finishing a lesson or island needs recorded answers and an unlocked island; auto DB backup before migrate; throttles on 15 more routes

- content: POST nodes/{id}/quiz/complete and lessons/{id}/complete refuse a locked island
  (403 node_locked, same rule as /api/home) and a user who has not answered every question
  (409 answers_missing). Before, only a user with zero hearts and no answers was refused, so
  anyone else finished any island, locked or not, and finishing a locked island's lessons
  unlocked it. A node or lesson with no questions still passes when unlocked, with no XP.
  The client can no longer understate totalQuestions to buy stars.
- throttle_scope on 15 routes that had none (question bank without login, intro, hearts,
  notifications, tickets, plans, subscription status, orders, offers, affiliate, assistant
  history and feedback, logout).
- admin: OTPCode and Session can only be added/changed by a superuser.
- deploy.sh: integrity-checked DB backup before migrate (keeps the last 2); no migrate without it.
- docs and CLAUDE.md updated to say what is verified and what is not.

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

accounts/admin.py

@@ -174,12 +174,26 @@ class SessionAdmin(admin.ModelAdmin):
     list_display = ('id', 'user', 'expires_at', 'revoked')
     list_filter = ('revoked',)
 
+    # ساختن/ویرایشِ دستیِ نشست یعنی ساختنِ ورود برای هر کاربر؛ فقط ابرکاربر.
+    def has_add_permission(self, request):
+        return request.user.is_superuser
+
+    def has_change_permission(self, request, obj=None):
+        return request.user.is_superuser
+
 
 @admin.register(OTPCode)
 class OTPCodeAdmin(admin.ModelAdmin):
     list_display = ('id', 'phone', 'code', 'expires_at', 'is_used')
     list_filter = ('is_used',)
 
+    # ردیفِ OTP که کارمند می‌سازد = ورود بی‌پیامک به هر شماره (راهِ تستر)؛ فقط ابرکاربر.
+    def has_add_permission(self, request):
+        return request.user.is_superuser
+
+    def has_change_permission(self, request, obj=None):
+        return request.user.is_superuser
+
 
 # صفحه‌ی «ناظر» (Supervisor): یک ایندکسِ read-only از لینک‌ها به
 # changelistهای موجود (کاربران/پرداخت‌ها/اشتراک‌ها)، داخلِ همون AdminSite