Document the new file search API

[sagikazarmark]

Preflight Checklist

• I have searched the issue tracker for an issue that matches the one I want to file, without success.

Problem Description

The new file search API introduced in 1.20 is not mentioned in the README.

Proposed Solution

Document it in the readme.

Alternatives Considered

No response

Additional Information

No response

[github-actions]

Issues with no activity for 30 days are marked stale and subject to being closed.

[sagikazarmark]

@spacez320 FYI if you are looking at documentation

[spacez320]

Sure, I can take this. Feel free to assign me.

[sagikazarmark]

Gonna add "/self-assign" to slash commands. ;)

[sagikazarmark]

/label area/documentation