Resolve remote custom module path warnings
Author: XuehaiPan
Pull request: yes

# What does this PR do?

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Fixes https://github.com/huggingface/transformers/pull/40809#issuecomment-3354623703


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Models:

- text models: @ArthurZucker @Cyrilvallez
- vision models: @yonigozlan @molbap
- audio models: @eustlb @ebezzam @vasqu
- multimodal models: @zucchini-nlp
- graph models: @clefourrier

Library:

- generate: @zucchini-nlp (visual-language models) or @gante (all others)
- continuous batching: @remi-or @ArthurZucker @McPatate
- pipelines: @Rocketknight1
- tokenizers: @ArthurZucker and @itazap
- trainer: @zach-huggingface @SunMarc
- attention: @vasqu @ArthurZucker @CyrilVallez
- model loading (from pretrained, etc): @CyrilVallez
- distributed: @3outeille @ArthurZucker @S1ro1
- CIs: @ydshieh

Integrations:

- deepspeed: HF Trainer/Accelerate: @SunMarc @zach-huggingface
- ray/raytune: @richardliaw, @amogkam
- Big Model Inference: @SunMarc
- quantization (bitsandbytes, autogpt): @SunMarc @MekkCyber
- kernels: @MekkCyber @drbh

Devices/Backends:

- AMD ROCm: @ivarflakstad
- Intel XPU: @IlyasMoutawwakil
- Ascend NPU: @ivarflakstad 

Documentation: @stevhliu

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cc @Rocketknight1 @st81

Comments:
Reviewing now - I'm confused why models like `SmolLM` trigger this code path at all, because they are not remote code models. I'm going to try to figure that out first.

Investigated, this is happening because of the `load_custom_generate()` call. This checks for a custom generation function in the model repo, which triggers the dynamic code utils paths. This unfortunately then triggers the warnings.

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_41243). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.