Custom slash commands from ~/.claude/commands/ not recognized

Description

Custom slash commands placed in ~/.claude/commands/ (global user commands) are not recognized when invoked.

Steps to Reproduce

1. Create a markdown file at ~/.claude/commands/find-issues.md with prompt content
2. Start a Claude Code session
3. The command appears in the /skills dialog
4. Try to invoke it as /find-issues → "Unknown skill: find-issues"
5. Try /user:find-issues → "Unknown skill: user:find-issues"

Expected Behavior

The command should be invocable as a slash command from any project, since it's in the global ~/.claude/commands/ directory.

Workaround

Copying the file to the project-local .claude/commands/ directory works — but this defeats the purpose of having a global commands directory.

Environment

• macOS (Darwin 25.2.0)
• Claude Code CLI (latest)