fix: align network map builder with account isolation

backend/app/schemas/device_type.py

@@ -30,7 +30,7 @@ class DeviceTypeResponse(BaseModel):
     label: str
     category: str
     is_system: bool
-    team_id: UUID | None = None
+    account_id: UUID
     sort_order: int
     created_at: datetime
 

backend/app/schemas/network_diagram.py

@@ -61,7 +61,7 @@ class NetworkDiagramUpdate(BaseModel):
 
 class NetworkDiagramResponse(BaseModel):
     id: UUID
-    team_id: UUID
+    account_id: UUID
     name: str
     client_name: str | None = None
     asset_name: str | None = None