[BUG] /command auto complete and @file auto complete do not work together

Environment

• Platform (select one):
• [ ] Anthropic API
• [ ] AWS Bedrock
• [ ] Google Vertex AI
• [X] Other: Claude code
• Claude CLI version: 1.0.17 (Claude Code)
• Operating System: Arch Linux
• Terminal: alacritty

Bug Description

When trying to use both /command and @file, claude code will only offer completion options for the first, but not the second.

Steps to Reproduce

1. Start typing a /command (e.g., /user:prd (this is a custom command I created to write a PRD)
2. Optionally add some more text after the command
3. Then try and refer to a file (e.g., @project_goal.txt).

Expected Behavior

I expect claude to give me a menu of files that will get filtered as a type.

Actual Behavior

The menu does not appear. There's no option to select a file from a list.

Additional Context

The reverse also does not work. If I first add a @file reference (which works) and then try to edit the start of the row to add a /command, it will not complete the /command.