Viewing assistant conversation history should not modify modified time

[failable]

Check for existing issues

• Completed

Describe the bug / provide steps to reproduce it

• Open the assistant conversation history
• Click an item other than the first one
• Do nothing and close the item
• Observation: The closed item is now the most recent one and the modified time is now.

That means viewing every item will change the history list. I would expect the history list is changed only if the item is updated or modified.

Environment

Zed: v0.158.1 (Zed Preview)
OS: macOS 15.0.1
Memory: 32 GiB
Architecture: x86_64

If applicable, add mockups / screenshots to help explain present your vision of the feature

No response

If applicable, attach your Zed.log file to this issue.

Zed.log