fix: Cloudflash now supports full-wipe before flashing

backend/firmware/service.py

@@ -390,9 +390,9 @@ def delete_firmware(doc_id: str) -> None:
             db.collection(COLLECTION)
             .where("hw_type", "==", hw_type)
             .where("channel", "==", channel)
-            .order_by("uploaded_at", direction="DESCENDING")
-            .limit(1)
             .stream()
         )
         if remaining:
+            # Sort in Python to avoid needing a composite Firestore index
+            remaining.sort(key=lambda d: d.to_dict().get("uploaded_at", ""), reverse=True)
             remaining[0].reference.update({"is_latest": True})