[Qwen Image 2.1] Fix vae tiling defaults

[asomoza]

For using vae tiling which is required to be able to run the model at high resoltuions with consumer GPUs, the default tiling values produce seams and even artifacts, this PR change the defaults values to the minimal ones that don't produce them.

no tiling	tiling main	tiling PR

For a 2048x2048 image like the one in the examples, it requires ~27GB of VRAM to decode it, with these values for tiling it requires ~4.4GB of VRAM. Any smaller sizes will produce the seams, at 512/256 they are thinner but I could still see them.

To reproduce this issue, just do inference with vae tiling.

@sayakpaul @naykun

[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.

[sayakpaul]

Okay for me. But let's see what @naykun has to say.