The API endpoint /conversations does not include an 'update_at' field

[rchlz]

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

I've found the pr for the 'updated_at' sorting in pull request https://github.com/langgenius/dify/pull/7348. This feature is great, but the response fields do not include 'updated_at'. I need to decide whether to start a new conversation based on the latest 'updated_at'. Is it possible to implement this functionality also，pr #7348 didn't get the api docs updated

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]

Feel free to adjust the docs, we are kind of busy these days.