dify - 💡(How to fix) Fix After clicking preview on a parent-child segmented knowledge base, it shows 0 chunks

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Dify version

0.14.2

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

When creating a knowledge base with parent-child segmentation, after clicking the preview button, it displays 0 chunks. <img width="1901" height="925" alt="Image" src="https://github.com/user-attachments/assets/44c4a969-4a42-4b50-9007-1a86a4ab25fc" />

✔️ Expected Behavior

It should display the chunks correctly.

❌ Actual Behavior

When creating a knowledge base with parent-child segmentation, after clicking the preview button, it displays 0 chunks.

<img width="1901" height="925" alt="Image" src="https://github.com/user-attachments/assets/82f68e95-f346-41d8-b399-d7ae87ee08ff" />