Fix: Tolerate missing?

projects/tentacles/src/tentacles/workers.py

@@ -87,7 +87,7 @@ def poll_printers(app: App, db: Db) -> None:
                     "reference": snapshots[0],
                 },
             )
-            similarity = status["similarity"] ** 3 # Cube it
+            similarity = status.get("similarity", 0.0) ** 3 # Cube it
             return similarity > 0.9
 
         printer_job = {}