Feat: Add OceanBase hybrid search features

[hsiong]

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

We are using OceanBase as the vector store(based on PyVctor), instead of Weaviate. Dify only support Vector search while using oceanbase. We've added support for full-text & hybrid search in Oceanbase. A PR will be submitted soon.

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2. Additional context or comments

No response

3. Can you help us with this feature?

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