fix: add debug logging for pvesm config per-pool to trace why images filter excludes pools

backend/app.py

@@ -119,8 +119,9 @@ def storage_pools():
                 for cl in cp.stdout.split("\n"):
                     if cl.strip().startswith("content"):
                         content = cl.strip().split(None, 1)[1] if len(cl.strip().split(None, 1)) > 1 else ""
-            except Exception:
-                pass
+                logger.info("  pool %s (%s) content=%r", name, stype, content)
+            except Exception as exc:
+                logger.warning("  pvesm config %s failed: %s", name, exc)
             if "images" not in content:
                 continue
             result.append({"name": name, "type": stype})