Добавлена локальная загрузка снапшота

interfaces/snapshot.go

@@ -38,6 +38,9 @@ type SnapshotManager interface {
 	// It returns an io.ReadCloser for the archive stream and an error.
 	// The caller is responsible for closing the reader, which will also handle cleanup of temporary resources.
 	StreamSnapshotDiff(ctx context.Context, snapshotID, parentID string, offset int64) (io.ReadCloser, error)
+
+	// GetSnapshotDiffInfo calculates the hash and size of a differential archive between two snapshots.
+	GetSnapshotDiffInfo(ctx context.Context, snapshotID, parentID string) (*store.DiffInfo, error)
 }
 
 // SnapshotServer defines the interface for a server that can share snapshots