convert : fix LoRA conversion crash for Qwen3.5 V-head reorder (#28324)

* convert: fix LoRA conversion crash for Qwen3.5 V-head reorder

_reorder_v_heads does reshape+permute+reshape to reorder V heads from
grouped to tiled order.  LoraTorchTensor.reshape() cannot split its
row dimension (A matrix), so converting Qwen3.5 LoRA adapters that
target out_proj crashes with NotImplementedError.

Fix: detect LoRA tensors and apply the equivalent index permutation
directly — column reorder (dim=last) permutes A's columns, row
reorder (dim=0) permutes B's rows.  This is mathematically identical:
  (B @ A)[:, perm] == B @ A[:, perm]
  (B @ A)[perm, :] == B[perm, :] @ A

Verified: both paths produce exactly zero diff against the full-tensor
reorder on random (rank=32, 4096×4096) matrices.

Fixes #21125

Signed-off-by: Radu Swigler <radu@swigler.com>

* convert: add ty: ignore for hasattr-guarded LoRA call

Assisted-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix comment

* nowrap

---------

Signed-off-by: Radu Swigler <radu@swigler.com>
Co-authored-by: Radu Swigler <radu@swigler.com>
Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@huggingface.co>
Assisted-by: Claude Opus 4.6 <noreply@anthropic.com>