Backend: synchronous print status on add_items

add_items now runs printer routing synchronously and returns
{ order, print_results } so the waiter PWA can show per-printer
ack or failure without guessing. Extracted _do_route_and_print
so the background-task path (route_and_print) is unchanged for
other callers.

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

local_backend/schemas/order.py

@@ -42,6 +42,22 @@ class OrderItemOut(BaseModel):
     status: str
     added_at: datetime
     printed: bool
+    paid_by: Optional[int] = None
+    paid_at: Optional[datetime] = None
+    payment_method: Optional[str] = None
+
+    model_config = {"from_attributes": True}
+
+
+class PrintResultOut(BaseModel):
+    printer_name: str
+    success: bool
+    error: Optional[str] = None
+
+
+class AddItemsResponse(BaseModel):
+    order: "OrderOut"
+    print_results: List[PrintResultOut]
 
     model_config = {"from_attributes": True}
 
@@ -52,6 +68,7 @@ class OrderCreate(BaseModel):
 
 class PayItemsRequest(BaseModel):
     item_ids: List[int]
+    payment_method: Optional[str] = None  # 'cash' | 'card' | 'other' — optional for now
 
 
 class AssignWaiterRequest(BaseModel):
@@ -63,6 +80,21 @@ class OrderWaiterOut(BaseModel):
     model_config = {"from_attributes": True}
 
 
+class AuditLogOut(BaseModel):
+    id: int
+    order_id: int
+    event_type: str
+    waiter_id: Optional[int] = None
+    waiter_name: Optional[str] = None   # resolved server-side
+    item_ids: Optional[str] = None
+    amount: Optional[float] = None
+    payment_method: Optional[str] = None
+    note: Optional[str] = None
+    created_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
 class OrderOut(BaseModel):
     id: int
     table_id: int
@@ -74,5 +106,6 @@ class OrderOut(BaseModel):
     notes: Optional[str] = None
     items: List[OrderItemOut] = []
     waiters: List[OrderWaiterOut] = []
+    audit_logs: List[AuditLogOut] = []
 
     model_config = {"from_attributes": True}