feat: Passwordless cross-device authentication

- Arkitektur: docs/auth/passwordless-architecture.md
- Backend: iom/quixzoom-auth-service/ (FastAPI + Redis)
- Webb: quixzoom-market-pages/se/login/ (QR-kod + polling)
- App: iom/quixzoom-app/src/features/auth/ (push + deep links)

Flöde: QR-kod → app-godkännande → webb-inloggad

iom/quixzoom-auth-service/models/device.py

@@ -0,0 +1,101 @@
+"""
+Device model for passwordless authentication
+Represents a registered mobile device (app)
+"""
+
+from datetime import datetime
+from typing import Optional
+from enum import Enum
+from pydantic import BaseModel, Field
+import uuid
+
+
+class DevicePlatform(str, Enum):
+    """Supported device platforms"""
+    IOS = "ios"
+    ANDROID = "android"
+    WEB = "web"
+    OTHER = "other"
+
+
+class DeviceStatus(str, Enum):
+    """Device status"""
+    ACTIVE = "active"
+    REVOKED = "revoked"
+    SUSPENDED = "suspended"
+
+
+class Device(BaseModel):
+    """Device database model"""
+    id: str = Field(default_factory=lambda: str(uuid.uuid4()))
+    user_id: str = Field(..., description="Associated user ID")
+    device_name: str = Field(..., description="Human-readable device name")
+    platform: DevicePlatform = Field(..., description="Device platform")
+    
+    # Device fingerprinting
+    public_key: str = Field(..., description="Device public key for challenge signing")
+    device_fingerprint: str = Field(..., description="Unique device fingerprint hash")
+    
+    # Metadata
+    push_token: Optional[str] = Field(None, description="Push notification token")
+    last_ip: Optional[str] = Field(None, description="Last known IP address")
+    last_user_agent: Optional[str] = Field(None, description="Last user agent")
+    
+    # Status
+    status: DeviceStatus = Field(default=DeviceStatus.ACTIVE)
+    
+    # Timestamps
+    created_at: datetime = Field(default_factory=datetime.utcnow)
+    updated_at: datetime = Field(default_factory=datetime.utcnow)
+    last_used_at: Optional[datetime] = Field(None)
+    
+    class Config:
+        json_schema_extra = {
+            "example": {
+                "id": "dev_123456789",
+                "user_id": "user_abc123",
+                "device_name": "iPhone 15 Pro",
+                "platform": "ios",
+                "public_key": "-----BEGIN PUBLIC KEY-----\n...",
+                "device_fingerprint": "sha256:abc123...",
+                "status": "active",
+                "created_at": "2024-01-15T10:30:00Z"
+            }
+        }
+
+
+class DeviceCreate(BaseModel):
+    """Request model for device registration"""
+    user_id: str = Field(..., description="User ID to associate with device")
+    device_name: str = Field(..., min_length=1, max_length=100)
+    platform: DevicePlatform
+    public_key: str = Field(..., min_length=100, description="Device public key")
+    device_fingerprint: str = Field(..., min_length=32, description="Device fingerprint")
+    push_token: Optional[str] = Field(None, max_length=500)
+
+
+class DeviceUpdate(BaseModel):
+    """Request model for device update"""
+    device_name: Optional[str] = Field(None, min_length=1, max_length=100)
+    push_token: Optional[str] = Field(None, max_length=500)
+    status: Optional[DeviceStatus] = None
+
+
+class DeviceResponse(BaseModel):
+    """Response model for device operations"""
+    id: str
+    user_id: str
+    device_name: str
+    platform: DevicePlatform
+    status: DeviceStatus
+    created_at: datetime
+    last_used_at: Optional[datetime] = None
+    
+    class Config:
+        from_attributes = True
+
+
+class DeviceListResponse(BaseModel):
+    """Response model for listing devices"""
+    devices: list[DeviceResponse]
+    total: int