Fix temporal persistence wiring and restore slurp_full suite

pkg/slurp/storage/errors.go

@@ -0,0 +1,8 @@
+package storage
+
+import "errors"
+
+// ErrNotFound indicates that the requested context does not exist in storage.
+// Tests and higher-level components rely on this sentinel for consistent handling
+// across local, distributed, and encrypted backends.
+var ErrNotFound = errors.New("storage: not found")

pkg/slurp/storage/local_storage.go

@@ -201,7 +201,7 @@ func (ls *LocalStorageImpl) Retrieve(ctx context.Context, key string) (interface
 	entryBytes, err := ls.db.Get([]byte(key), nil)
 	if err != nil {
 		if err == leveldb.ErrNotFound {
-			return nil, fmt.Errorf("key not found: %s", key)
+			return nil, fmt.Errorf("%w: %s", ErrNotFound, key)
 		}
 		return nil, fmt.Errorf("failed to retrieve data: %w", err)
 	}
@@ -328,7 +328,7 @@ func (ls *LocalStorageImpl) Size(ctx context.Context, key string) (int64, error)
 	entryBytes, err := ls.db.Get([]byte(key), nil)
 	if err != nil {
 		if err == leveldb.ErrNotFound {
-			return 0, fmt.Errorf("key not found: %s", key)
+			return 0, fmt.Errorf("%w: %s", ErrNotFound, key)
 		}
 		return 0, fmt.Errorf("failed to get data size: %w", err)
 	}