[Bug]: Empty search create infinite loading + error 400

Before you file a bug report

• I have checked the issue tracker and have not found an issue that matches the one I'm filing.
• This issue is not a troubleshooting question. Troubleshooting questions go here: https://forum.mattermost.com/c/trouble-shoot/16.
• This issue is not a feature request. You can request features and make product suggestions here: https://mattermost.uservoice.com/forums/306457-general/.
• This issue reproduces on one of the currently supported server versions.
• I have read the contribution guidelines and the Mattermost Handbook Contribution Guidelines.

Mattermost Server Version

10.9.0

Operating System

macOS

Steps to reproduce

• Press Enter in the search bar while the input is empty

Expected behavior

Either:

• Prevent pressing Enter when the input is empty, or

• Allow an empty search without triggering an error (i.e., display no results)

Observed behavior

• An infinite loading spinner appears

• A 400 Bad Request error is triggered in the console

Log Output

Additional Information

https://github.com/user-attachments/assets/4edaa64e-1a86-4fb3-837d-4f050f08b541