[BUG] Slash command autocomplete doesn't filter candidates when typing after /

Description

After typing / in the input, the slash command autocomplete menu appears correctly. However, continuing to type characters does not filter/search the command list. The menu remains showing all commands regardless of what is typed after /.

Steps to Reproduce

1. Start a Claude Code session
2. Type / in the input field
3. The autocomplete menu appears (correct)
4. Continue typing, e.g. /com to filter for /commit or /compact
5. Expected: The menu filters to show only matching commands
6. Actual: The menu does not filter — all commands remain visible

Environment

• Claude Code version: 2.1.44 (Homebrew cask)
• OS: macOS Darwin 25.3.0
• Terminals tested: Ghostty, Terminal.app (issue reproduced in both)
• Vim mode: Disabled
• Input method: English (no IME interference)
• Custom keybindings: Standard Autocomplete bindings (tab/escape/up/down), no conflicts

Debug Log

No [ERROR] or [WARN] entries related to slash commands or autocomplete in the session debug log. All skills and commands load successfully:

Loaded 13 unique skills (13 unconditional, 0 conditional, managed: 0, user: 8, project: 1, additional: 0, legacy commands: 4)
Plugin skills: 1, Plugin commands: 2, Bundled skills: 2

Workaround

• Use arrow keys to manually navigate to the desired command
• Type the full command name and press Enter