t3_rank_adjustment_sweep
========================

.. py:function:: t3toolbox.backend.t3_svd.t3_rank_adjustment_sweep(x, direction = 'right_to_left')

   .. code-block:: python

      def t3_rank_adjustment_sweep(
              x: typ.Tuple[
                  typ.Tuple[NDArray, ...],  # tucker_cores
                  typ.Tuple[NDArray, ...],  # tt_cores
              ],
              direction: str = 'right_to_left',  # 'right_to_left' | 'left_to_right'
      ) -> typ.Tuple[
          typ.Tuple[NDArray, ...],  # tucker_cores
          typ.Tuple[NDArray, ...],  # tt_cores
      ]:


   A single lossless directional sweep that drops structurally-redundant ranks (re-SVD each Tucker
   edge and TT bond with **no cap**). The represented tensor is unchanged.

   ``'right_to_left'`` produces a **right-orthogonal** result; ``'left_to_right'`` a **left-orthogonal**
   one. A single sweep reaches the minimal ranks **only if the input is already orthogonal in the
   opposite direction** -- e.g. a :py:func:`t3svd` result is left-orthogonal, so
   ``t3_rank_adjustment_sweep(result, 'right_to_left')`` minimizes it (verify with ``has_minimal_ranks``).
   On a general input it is a partial reduction; compose both directions for guaranteed minimal ranks.