fix(Qwen3VLCausalLMOutputWithPast): missing `hidden_states` and `atte…
Author: casinca
Pull request: yes

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Fixes https://github.com/huggingface/transformers/issues/42594

As it was discussed in the issue, I've added the missing `hidden_states`  kwarg but also `attentions` to keep consistency with the other Qwen2 VL and 2.5 VL signatures and replaced the decorator based on what @zucchini-nlp said.

```diff
        return Qwen3VLModelOutputWithPast(
            last_hidden_state=outputs.last_hidden_state,
            past_key_values=outputs.past_key_values,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
            rope_deltas=self.rope_deltas,
        )
```

&nbsp;

If the PR is good, I will also update the signature for `modular_qwen3_vl_moe.py`? it seems to be missing there too.

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I'm tagging @Rocketknight1 and @zucchini-nlp  since you were discussing on the issue.

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Models:

- text models: @ArthurZucker @Cyrilvallez
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Comments:
I've reverted for the base model and re-generated the modeling files. Concerning my initial question since `modeling_qwen3_vl_moe.py` got updated for the decorator swap, should I also add the kwargs in https://github.com/huggingface/transformers/blob/9b74e4c43402049608fc3e74c9b675d9b37ef0f7/src/transformers/models/qwen3_vl_moe/modular_qwen3_vl_moe.py#L494-L500

`make fix-copies` again and it's good? 

@casinca yes, you would need to update the VL-MoE model in the same way. I see a few tests failing with the MoE model rn

**[For maintainers]** Suggested jobs to run (before merge)

run-slow: qwen3_vl, qwen3_vl_moe

> @casinca yes, you would need to update the VL-MoE model in the same way. I see a few tests failing with the MoE model rn

I made the changes for `modular_qwen3_vl_moe.py`, all tests passed for both VL archs now

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