feat: initial commit — local services (backend + manager dashboard + waiter PWA)

Includes all work to date:
- local_backend: FastAPI backend with products, orders, tables, shifts, cloud sync
- manager_dashboard: React manager UI with product/category management, reports, settings
- waiter_pwa: React PWA for waiter devices
- Category reparent endpoint and UI
- Waiter domain: local_ip sent on heartbeat, waiter_domain persisted from cloud response
- QR code modal in AppInfoTab for waiter domain
- Product form: number input spinners removed, category pre-selected on new product
- Category row: count badge moved to far right

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

local_backend/schemas/printer.py

@@ -0,0 +1,31 @@
+from pydantic import BaseModel
+from typing import Optional
+
+
+PROTOCOLS = ["escpos_tcp"]  # extend later as needed
+
+
+class PrinterBase(BaseModel):
+    name: str
+    ip_address: str
+    port: int = 9100
+    is_active: bool = True
+    protocol: str = "escpos_tcp"
+
+
+class PrinterCreate(PrinterBase):
+    pass
+
+
+class PrinterUpdate(BaseModel):
+    name: Optional[str] = None
+    ip_address: Optional[str] = None
+    port: Optional[int] = None
+    is_active: Optional[bool] = None
+    protocol: Optional[str] = None
+
+
+class PrinterOut(PrinterBase):
+    id: int
+
+    model_config = {"from_attributes": True}