add Ollama rerank model

[shenhai-ran]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

Hi, I am trying to use Ollama only with Dify, and I am missing rerank models in the usecase of RAG. Could you please add rerank models for Ollama, besides LLM and text embedding.

2. Additional context or comments

No response

3. Can you help us with this feature?

• [X] I am interested in contributing to this feature.

[crazywoola]

I do not see rerank type here https://www.ollama.com/search.

[shenhai-ran]

@crazywoola yes, you are absolutely right. But now Ollama supports models from Huggingface, as in this blog https://huggingface.co/docs/hub/en/ollama, and there are rerank model of GGUF format on Huggingface, such as https://huggingface.co/gpustack/bge-reranker-v2-m3-GGUF.

Do you think Dify can support that?