feat: custom roles with per-permission matrix for café owners

- Owner can define named custom roles (e.g. Barista, Supervisor) with
  color, description, and a fine-grained permission set (21 permissions
  across 7 categories: admin, menu, staff, customer, reports, ops, kitchen)
- Employee assigned a custom role gets its permissions embedded in the
  JWT at login (customPerms claim) and parsed by TenantMiddleware —
  overrides the static EmployeeRole matrix for all API permission checks
- New endpoints: GET/POST/PATCH/DELETE /api/cafes/{id}/custom-roles and
  PUT /api/cafes/{id}/employees/{id}/custom-role for assignment
- Dashboard Settings → Team & Staff → Custom Roles panel with grouped
  checkbox matrix, group-level toggles, color preset picker, CRUD forms,
  and employee-count display; translations in fa/en/ar
- EF migration adds CustomRoles table + nullable CustomRoleId FK on Employees
- POS slip now shows per-item notes on both thermal print and bill preview

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/dashboard/messages/fa.json

@@ -1276,7 +1276,54 @@
       "printer": "پرینتر",
       "printerSettings": "تنظیمات پرینتر",
       "printTest": "صفحه تست چاپ",
-      "shopDiscover": "کشف و AI"
+      "shopDiscover": "کشف و AI",
+      "team": "تیم و کارمندان",
+      "customRoles": "نقش‌های سفارشی"
+    },
+    "customRoles": {
+      "title": "نقش‌های سفارشی",
+      "subtitle": "نقش‌هایی با دسترسی دلخواه برای کارمندان تعریف کنید",
+      "newRole": "نقش جدید",
+      "editRole": "ویرایش نقش",
+      "name": "نام نقش",
+      "namePlaceholder": "مثلاً: باریستا، مسئول طبقه",
+      "description": "توضیح (اختیاری)",
+      "descriptionPlaceholder": "توضیح مختصر درباره این نقش",
+      "color": "رنگ",
+      "permissions": "دسترسی‌ها",
+      "empty": "هنوز نقش سفارشی تعریف نشده است",
+      "saveError": "ذخیره نقش ناموفق بود",
+      "deleteConfirm": "نقش «{name}» حذف شود؟ این کارمندان به دسترسی پیش‌فرض نقش اصلی خود بازمی‌گردند.",
+      "groupAdmin": "مدیریت کافه",
+      "groupMenu": "منو و انبار",
+      "groupStaff": "پرسنل",
+      "groupCustomer": "مشتری و میز",
+      "groupReports": "گزارش و مالی",
+      "groupOps": "عملیات صندوق",
+      "groupKitchen": "آشپزخانه و تحویل",
+      "perm": {
+        "ManageCafeSettings": "تنظیمات کافه",
+        "ManageBilling": "اشتراک و پرداخت",
+        "ManageBranches": "مدیریت شعب",
+        "ManageMenu": "مدیریت منو",
+        "ManageInventory": "انبار و موجودی",
+        "ManageTaxes": "مالیات",
+        "ManagePrintSettings": "تنظیمات چاپ",
+        "ManageStaff": "مدیریت کارمندان",
+        "ManageSalaries": "حقوق و دستمزد",
+        "ReviewLeave": "بررسی مرخصی",
+        "ManageReservations": "رزروها",
+        "ManageTables": "میزها",
+        "ManageCoupons": "کوپن‌ها",
+        "ViewReports": "گزارش‌ها",
+        "ManageExpenses": "هزینه‌ها",
+        "ProcessOrders": "ثبت سفارش",
+        "HandlePayments": "پردازش پرداخت",
+        "OperateRegister": "صندوق",
+        "ManageQueue": "صف انتظار",
+        "ViewKitchen": "نمایش آشپزخانه",
+        "HandleDelivery": "تحویل و پیک"
+      }
     },
     "appearance": {
       "paletteSection": "پالت رنگ",