Add search result sorting and grouping

[samhu1]

Summary

Search results are useful, but they would be easier to scan if they were grouped and sorted more intentionally, especially once date filtering exists.

Acceptance Criteria

• Group or sort session-title hits and message hits consistently.
• Make result timestamps easier to interpret.
• Preserve performance for existing search usage.
• Keep the UI readable in narrow sidebars or compact layouts.

[shogun444]

Hi! I’d like to work on this.

I’m planning to improve the search results by grouping session title matches and message matches clearly, and then sorting them in a consistent way (likely by recency). I’ll also make the timestamps easier to read and ensure the layout stays clean and usable even in compact views.

I’ll keep performance in mind while restructuring the results so existing search behavior isn’t affected.

Let me know if you have any specific preferences for grouping or sorting, otherwise I’ll start with this approach.