Slash command autocomplete highlights wrong item that doesn't match search query

Description

When typing a slash command in the CLI, the autocomplete dropdown highlights the wrong item. The highlighted item doesn't match the search query.

Steps to Reproduce

1. Start Claude Code CLI
2. Type /resu (partial match for /resume)
3. Observe the autocomplete dropdown

Expected Behavior

• The dropdown should highlight /resume since it matches the search query "resu"
• Or only show filtered results that match the query

Actual Behavior

• /o365 is highlighted at the top even though it contains none of the characters from "resu"
• The highlighting appears to default to the first item in the unfiltered list rather than the first matching item

Screenshot

!autocomplete-bug

Environment

• Claude Code v2.1.5
• Opus 4.5
• Windows

Additional Context

The filtering logic may be working (various commands are shown), but the selection/highlight logic seems to be operating on the original unfiltered list index rather than the filtered results.