[Feature Request] Add 'has attachment' filter to session search

Feature Request

Add the ability to filter/search Claude Code sessions by whether they contain attachments (e.g., images, files).

Use case

When looking through past sessions, it would be helpful to narrow results to only sessions where files or images were attached. This makes it easier to find specific conversations where visual context or file references were shared.

Suggested behavior

A filter option like has:attachment or a checkbox/toggle in the session search UI that limits results to sessions containing attachments.