[DOCS]: API Doc update and add

[xiangshaonumber1]

Type of Documentation Change

Content update

Documentation Page URL or Path

https://docs.dify.ai/api-reference/models/get-available-embedding-models

Current Content

Suggested Changes

I found that there is only an API for obtaining the embedding model, but during operation, I also need the API interface for the rerank model, which I have not seen yet. I hope to add new interfaces and documentation
Based on this, it was also found that many APIs for other functions are missing, such as the API for the [Preview Block] function
As a source platform, dify also provides APIs, which is a great decision. However, the lack of API documentation also brings certain difficulties to users. We hope to strengthen the maintenance of documentation, which is really important

Reason for Change

No response

Code of Conduct

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[dosubot]

Hi, @xiangshaonumber1. I'm Dosu, and I'm helping the dify-docs team manage their backlog and am marking this issue as stale.

Issue Summary:

• You requested API documentation for the rerank model and other missing functions like the Preview Block.
• Currently, only the embedding model API is documented.
• The goal is to have comprehensive API docs to improve the user experience on the Dify platform.
• There has been no further activity or comments on this issue since it was opened.

Next Steps:

• Please let me know if this issue is still relevant to the latest version of the dify-docs repository by commenting here.
• If I do not hear from you, this issue will be automatically closed in 5 days.

Thank you for your understanding and contribution!