Add Wan with STG as a community pipeline

[Ednaordinary]

What does this PR do?

This adds Wan with STG as a community pipeline. The original paper does not cover wan, but it could be a useful addition. Comparison between Wan 1.3b (nf4 bnb quantized) with stg [3, 8, 16] at scale ((1/3)*1.1) and without stg:

STG

output_stg.mp4

No STG

output_no_stg.mp4

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

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@yiyixuxu @a-r-r-o-w

[a-r-r-o-w]

Hey, awesome work! Thanks for the Wan STG example 🤗

Could you update the table in community README to mention this addition is by you?https://github.com/huggingface/diffusers/blob/main/examples/community/README.md

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[Ednaordinary]

Done, though I'm not sure if its in the best place since I'm not an author on the original paper. Also, I fixed a typo in the example (since stg_mode isnt supported in diffusers)

[yiyixuxu]

@bot/ style

[a-r-r-o-w]

@bot /style

[github-actions]

Style fixes have been applied. View the workflow run here.

[a-r-r-o-w]

@hlky @DN6 do we know why there's no option to trigger tests after style fixes are applied from the bot?

[asomoza]

@a-r-r-o-w https://huggingface.slack.com/archives/C065E480NN9/p1742487925713499

I'm using empty commits to fix it for now.

[Ednaordinary]

that help?

[a-r-r-o-w]

Yep thanks for merging main. I've triggered the tests 🤗