Sparse dot meta now includes batch dimensions
Sparse dot meta now includes batch dimensions

Before this change, sparse dot metadata didn't include batch dimensions (as it's the same across batches).
After this change, sparse dot metadata has the shape that is similar to the sparse operand (all dimensions are the same, except the contracting minor dimension).

This allows implementing split-k pass that splits the contracting dimension into batch/contracting, without losing the metadata.
