feat(connect): Phase 3 — cloud API routes for Xenia Connect

Adds four new routers, three schema files, and one new model.
All new endpoints use new URL prefixes — no existing routes touched.

routers/menu.py
  GET  /api/menu/{site_slug}     — public menu snapshot (no auth)
  POST /api/menu/sync            — upsert snapshot (site API key)

routers/orders.py
  POST /api/orders/{site_slug}         — customer places order (public)
  GET  /api/orders/status/{public_ref} — customer tracks order (public)
  GET  /api/orders/pending/{site_id}   — local backend polls (site key)
  POST /api/orders/{id}/synced         — mark synced (site key)
  PATCH /api/orders/{id}/status        — update status with transition
                                         validation (site key)

routers/manager_auth.py
  POST /api/manager/register  — create manager account (admin JWT)
  POST /api/manager/login     — returns manager JWT
  POST /api/manager/refresh   — refreshes manager JWT
  Shared _get_current_manager dependency used by remote_dashboard

routers/remote_dashboard.py
  GET  /api/remote/sites                           — manager JWT
  GET  /api/remote/sites/{id}/snapshot             — manager JWT
  GET  /api/remote/sites/{id}/orders               — manager JWT
  GET  /api/remote/sites/{id}/orders/pending       — manager JWT
  PATCH /api/remote/sites/{id}/orders/{oid}/status — manager JWT
  POST /api/remote/snapshot                        — site API key
                                                     (stats push)

models/stats_snapshot.py (NEW)
  stats_snapshots table — one row per site, holds serialized
  operational stats; created by create_all on startup

config.py / .env.example
  MANAGER_JWT_SECRET and MANAGER_JWT_EXPIRE_HOURS (default 72h)
  added as separate settings from the admin SECRET_KEY

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

cloud_backend/schemas/online_order.py

@@ -0,0 +1,63 @@
+from __future__ import annotations
+from datetime import datetime
+from typing import Optional
+from pydantic import BaseModel
+
+
+class OrderItemIn(BaseModel):
+    product_id: int
+    name: str
+    quantity: int
+    unit_price: float
+    options: list = []
+
+
+class OnlineOrderCreate(BaseModel):
+    order_type: str                         # "delivery" | "dine_in"
+    customer_name: str
+    customer_phone: Optional[str] = None
+    customer_address: Optional[str] = None
+    customer_notes: Optional[str] = None
+    items: list[OrderItemIn]
+    subtotal: float
+    delivery_fee: float = 0.0
+    total: float
+
+
+class OnlineOrderCreated(BaseModel):
+    order_id: int
+    public_ref: str
+    status: str
+
+
+class OrderStatusOut(BaseModel):
+    public_ref: str
+    status: str
+    rejection_reason: Optional[str] = None
+
+
+class PendingOrderOut(BaseModel):
+    id: int
+    public_ref: str
+    order_type: str
+    customer_name: str
+    customer_phone: Optional[str] = None
+    customer_address: Optional[str] = None
+    customer_notes: Optional[str] = None
+    items_json: str
+    subtotal: float
+    delivery_fee: float
+    total: float
+    status: str
+    created_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class OrderSyncedRequest(BaseModel):
+    local_order_id: int
+
+
+class OrderStatusUpdateRequest(BaseModel):
+    status: str
+    rejection_reason: Optional[str] = None