Validate npz after prefetch

scripts/stream_train_autoloop.py

@@ -120,9 +120,22 @@ def _prefetch_uid(uid: str, token: str) -> bool:
                 got_render = True
             except Exception:
                 continue
-        if not got_render:
-            _log(f"UYARI: {uid} render yok, siyah pad ile devam")
-        return (dest / "geometry_latent.npz").exists()
+        if not (dest / "geometry_latent.npz").exists():
+            return False
+        # Bozuk npz'yi erken yakala
+        try:
+            import numpy as np
+
+            with np.load(dest / "geometry_latent.npz") as z:
+                _ = z["vertex_hist"]
+        except Exception as exc:
+            _log(f"Bozuk latent silindi uid={uid}: {exc}")
+            try:
+                (dest / "geometry_latent.npz").unlink(missing_ok=True)
+            except OSError:
+                pass
+            return False
+        return True
     except Exception as exc:
         msg = str(exc).lower()
         if "429" in msg or "rate limit" in msg: