feat: add DiffSynth backend support

[mysuochao2-boop]

No description provided.

[gemini-code-assist]

Code Review

This pull request introduces support for the DiffSynth backend, enabling built-in image and video generation. It includes localized configuration strings, a new parameters definition file, and logic to automatically select DiffSynth for image models while disabling distributed inference for it. The review feedback highlights a robustness issue in checkIsImageModel when handling string-based categories or comma-separated tasks. Additionally, the reviewer suggests extending the distributed inference exclusion logic to also cover the voxBox backend for consistency across the UI and form submission.

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[gemini-code-assist]

The checkIsImageModel function has potential robustness issues:

1. categories can be a string (e.g., 'image') or an array. If it is a string, calling .includes() performs a substring check, which can lead to false positives (e.g., 'image_only' would match 'image').
2. task can be a comma-separated string of tasks (especially for ModelScope models, e.g., 'text-to-image,image-to-image'). An exact equality check task === ModelscopeTaskMap[...] will fail when multiple tasks are present.

We should split task by , and check if the resulting array contains the target task, and handle categories safely by checking if it is an array or string.

  const checkIsImageModel = (model: any, source?: string) => {
    const task = model?.task;
    const categories = model?.categories || [];
    const hasImageCategory = Array.isArray(categories)
      ? categories.includes(modelTaskMap.image) || categories.includes(modelTaskMap.textToImage)
      : categories === modelTaskMap.image || categories === modelTaskMap.textToImage;

    if (
      model?.image_only ||
      hasImageCategory
    ) {
      return true;
    }

    const tasks = typeof task === 'string' ? task.split(',').map((t: string) => t.trim()) : [];

    if (source === modelSourceMap.huggingface_value) {
      return tasks.includes(HuggingFaceTaskMap[modelTaskMap.textToImage]);
    }
    if (source === modelSourceMap.modelscope_value) {
      return tasks.includes(ModelscopeTaskMap[modelTaskMap.textToImage]);
    }
    return (
      tasks.includes(modelTaskMap.textToImage) ||
      tasks.includes(modelTaskMap.image)
    );
  };

[gemini-code-assist]

Like diffSynth, the voxBox backend also does not support distributed inference across workers (and is forced to false on submit). We should exclude both diffSynth and voxBox from showing this option in the UI to keep it consistent.

Suggested change

	{currentBackendOptions?.isBuiltIn &&
	backend !== backendOptionsMap.diffSynth && (
	{currentBackendOptions?.isBuiltIn &&
	![backendOptionsMap.diffSynth, backendOptionsMap.voxBox].includes(backend) && (

[gemini-code-assist]

Unify the distributed inference configuration helper to also disable it for voxBox, as it is not supported by voxBox either.

Suggested change

	const updateDistributedInferenceConfig = (backend: string) => {
	if (backend === backendOptionsMap.diffSynth) {
	return {
	distributed_inference_across_workers: false
	};
	}
	return {};
	};
	const updateDistributedInferenceConfig = (backend: string) => {
	if ([backendOptionsMap.diffSynth, backendOptionsMap.voxBox].includes(backend)) {
	return {
	distributed_inference_across_workers: false
	};
	}
	return {};
	};

[gemini-code-assist]

Ensure distributed_inference_across_workers is forced to false on submit for both diffSynth and voxBox backends.

Suggested change

	...(data.backend === backendOptionsMap.diffSynth
	? { distributed_inference_across_workers: false }
	: {}),
	...([backendOptionsMap.diffSynth, backendOptionsMap.voxBox].includes(data.backend)
	? { distributed_inference_across_workers: false }
	: {}),