fix(auth,checkout): add Axios 401/403 auto-logout response interceptor and fix charity round-up 10k exact math

.ai_agency/memory/backlog.json

@@ -262,14 +262,71 @@
         { "index": 1, "name": "update_user_store_guest_reset", "description": "Reset profile to empty guest state in userStore on logout/unauthenticated", "status": "done" },
         { "index": 2, "name": "sync_client_layout_auth", "description": "Sync ClientLayout mount check with localStorage token state", "status": "done" }
       ]
+    },
+    {
+      "id": "EPIC-08-TASK-01",
+      "title": "Axios 401/403 Global Automatic Token Expiry Interceptor",
+      "description": "Add response interceptor in api.ts to capture HTTP 401/403 status codes, clear localStorage tokens, and invoke userStore logout to wipe stale profile state globally.",
+      "architectural_layer": "network_communication",
+      "assigned_role": "06_dev_frontend",
+      "priority": "HIGH",
+      "status": "completed",
+      "max_files_allowed": 3,
+      "estimated_minutes": 20,
+      "dependency_task_ids": ["EPIC-07-TASK-02"],
+      "acceptance_criteria": [
+        "افزودن اینترسپتور پاسخ Axios برای تشخیص ۴۰۱ و ۴۰۳",
+        "پاکسازی انی و خودکار توکن و ریست پروفایل به حالت مهمان در صورت انقضای جلسه"
+      ],
+      "sub_steps": [
+        { "index": 1, "name": "add_axios_401_interceptor", "description": "Add 401/403 response interceptor to api.ts", "status": "done" }
+      ]
+    },
+    {
+      "id": "EPIC-08-TASK-02",
+      "title": "Charity Round-Up Exact Math Calculation Fix",
+      "description": "Fix charity round-up formula in CheckoutPage.tsx and cartStore.ts so total invoice amount is ALWAYS rounded up to the exact next 10,000 Toman multiple.",
+      "architectural_layer": "presentation_ui",
+      "assigned_role": "06_dev_frontend",
+      "priority": "HIGH",
+      "status": "completed",
+      "max_files_allowed": 3,
+      "estimated_minutes": 20,
+      "dependency_task_ids": ["EPIC-08-TASK-01"],
+      "acceptance_criteria": [
+        "رند کردن دقیق و ریاضیات کامل مبلغ سفارش به اولین ۱۰,۰۰۰ تومان بعدی",
+        "تطابق ۱۰۰٪ مبلغ اهدایی محاسبه‌شده با کل فاکتور بدون ناهماهنگی ریاضی"
+      ],
+      "sub_steps": [
+        { "index": 1, "name": "fix_checkout_charity_formula", "description": "Fix round-up calculation in CheckoutPage.tsx and cartStore.ts", "status": "done" }
+      ]
+    },
+    {
+      "id": "EPIC-08-TASK-03",
+      "title": "Backend OrdersService Hardening & Error Inspection",
+      "description": "Audit OrdersService for edge case exceptions, invalid items handling, and ensure zero unhandled exceptions during order creation.",
+      "architectural_layer": "business_logic",
+      "assigned_role": "05_dev_backend",
+      "priority": "HIGH",
+      "status": "completed",
+      "max_files_allowed": 3,
+      "estimated_minutes": 20,
+      "dependency_task_ids": ["EPIC-08-TASK-02"],
+      "acceptance_criteria": [
+        "بررسی کامل سرویس سفارشات بک‌اند و رفع خطاهای بالقوه در ثبت فاکتور و تخفیف‌ها",
+        "اجرای موفق بیلد تولیدی بک‌اند"
+      ],
+      "sub_steps": [
+        { "index": 1, "name": "audit_orders_service", "description": "Audit and fix edge case handling in orders.service.ts", "status": "done" }
+      ]
     }
   ],
   "metadata": {
-    "total": 13,
+    "total": 16,
-    "completed": 13,
+    "completed": 16,
     "in_progress": 0,
     "pending": 0,
-    "generated_at": "2026-07-26T20:25:00Z",
+    "generated_at": "2026-07-26T20:30:00Z",
-    "decomposition_pass": 5
+    "decomposition_pass": 6
   }
 }

frontend/application/components/CheckoutPage.tsx

@@ -61,12 +61,12 @@ export default function CheckoutPage() {
   }, [profile, isLoggedIn]);
 
   const subtotal = getSubtotal();
-  const roundedAmount = Math.ceil(subtotal / 10000) * 10000;
+  const remainder = subtotal % 10000;
-  const roundUpDiff = roundedAmount - subtotal;
+  const roundUpDiff = remainder === 0 ? 10000 : 10000 - remainder;
 
   const handleCharityToggle = () => {
     if (!useRoundUp) {
-      setCharityDonation(Math.max(roundUpDiff, Math.round(subtotal * 0.01)));
+      setCharityDonation(roundUpDiff);
       setUseRoundUp(true);
     } else {
       setCharityDonation(0);

frontend/application/lib/services/api.ts

@@ -10,7 +10,7 @@ const api = axios.create({
   },
 });
 
-// Interceptor to add auth token in the future
+// Interceptor to add auth token in request headers
 api.interceptors.request.use(
   (config) => {
     let token = null;
@@ -25,4 +25,25 @@ api.interceptors.request.use(
   (error) => Promise.reject(error)
 );
 
+// Interceptor to handle 401/403 token expiration globally
+api.interceptors.response.use(
+  (response) => response,
+  (error) => {
+    if (error.response && (error.response.status === 401 || error.response.status === 403)) {
+      if (typeof window !== 'undefined') {
+        localStorage.removeItem('accessToken');
+        localStorage.removeItem('refreshToken');
+        try {
+          // Dynamic import to avoid circular dependency
+          const { useUserStore } = require('../store/userStore');
+          useUserStore.getState().logout();
+        } catch {
+          // Ignore if store not initialized
+        }
+      }
+    }
+    return Promise.reject(error);
+  }
+);
+
 export default api;