feat: printer duplicate copies setting (Feature 1)

- Add `duplicates` column (0-9) to printers table via migration
- Print loop repeats job 1+duplicates times per printer zone
- PrinterForm in Settings > Print now has ΑΝΤΙΓΡΑΦΑ (0-9) field
- PrinterRow shows amber badge when duplicates > 0

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

local_backend/main.py

@@ -406,6 +406,8 @@ def _run_migrations():
             created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
             priority VARCHAR NOT NULL DEFAULT 'normal'
         )""",
+        # Printer duplicate copies (0 = print once, 1 = print twice, etc.)
+        "ALTER TABLE printers ADD COLUMN duplicates INTEGER NOT NULL DEFAULT 0",
     ]
     for sql in migrations:
         try:

local_backend/models/printer.py

@@ -13,6 +13,7 @@ class Printer(Base):
     is_active = Column(Boolean, default=True, nullable=False)
     protocol = Column(String, default="escpos_tcp", nullable=False)
     line_width = Column(Integer, default=48, nullable=False)
+    duplicates = Column(Integer, default=0, nullable=False)
 
     products = relationship("Product", back_populates="printer_zone")
     print_logs = relationship("PrintLog", back_populates="printer")

local_backend/schemas/printer.py

@@ -12,6 +12,7 @@ class PrinterBase(BaseModel):
     is_active: bool = True
     protocol: str = "escpos_tcp"
     line_width: int = 48
+    duplicates: int = 0
 
 
 class PrinterCreate(PrinterBase):
@@ -25,6 +26,7 @@ class PrinterUpdate(BaseModel):
     is_active: Optional[bool] = None
     protocol: Optional[str] = None
     line_width: Optional[int] = None
+    duplicates: Optional[int] = None
 
 
 class PrinterOut(PrinterBase):

local_backend/services/printer_service.py

@@ -1256,10 +1256,12 @@ def _do_route_and_print(order_id: int, item_ids: List[int], db: Session) -> List
 
         success = False
         error_msg = None
+        copies = 1 + max(0, printer.duplicates or 0)
         try:
-            p = _get_printer(printer.ip_address, printer.port)
-            _print_kitchen_ticket(p, order, zone_items, db, printer.line_width)
-            p.close()
+            for _ in range(copies):
+                p = _get_printer(printer.ip_address, printer.port)
+                _print_kitchen_ticket(p, order, zone_items, db, printer.line_width)
+                p.close()
             success = True
             for item in zone_items:
                 item.printed = True