Add COD-in-transit summary and received tab to the dashboard

- GET /orders/summary: count and sum of cash-on-delivery for parcels not
  yet picked up (excludes received, refused, deleted/unknown TTNs, paid COD);
  shown as a card above the tabs.
- New «Полученные» tab: orders with NP received codes (9, 10, 11, 106) move
  there automatically, regardless of receipt; 106 is now a final status.

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

backend/app/api/v1/orders.py

@@ -6,7 +6,7 @@ from fastapi import APIRouter, Depends, HTTPException, Request, status
 
 from app.api.deps import CashierUser, CrmClientDep, SessionDep, require_any
 from app.db.models.audit import AuditAction
-from app.schemas.orders import OrderRowOut, OrderUpdateIn
+from app.schemas.orders import OrderRowOut, OrdersSummaryOut, OrderUpdateIn
 from app.services import audit
 from app.services import orders as orders_service
 from app.services import receipts as receipts_service
@@ -29,6 +29,14 @@ async def list_orders(
     return [OrderRowOut.from_order(order, receipts.get(order.id)) for order in orders]
 
 
+@router.get("/summary", response_model=OrdersSummaryOut)
+async def orders_summary(session: SessionDep) -> OrdersSummaryOut:
+    count, kopecks = await orders_service.cod_in_transit(session)
+    return OrdersSummaryOut(
+        cod_in_transit_count=count, cod_in_transit_amount=f"{kopecks / 100:.2f}"
+    )
+
+
 @router.patch("/{order_id}", response_model=OrderRowOut, response_model_by_alias=False)
 async def update_order(
     order_id: str,