User-level skills appear in slash-command autocomplete once per enabled plugin (N plugins = N duplicates)

Describe the bug

A user-level skill installed at ~/.claude/skills/<name>/SKILL.md appears in the slash-command autocomplete (/) once per enabled plugin rather than once globally. With 5 enabled plugins, the same skill shows up 5 times with identical descriptions. A user-level command at ~/.claude/commands/<name>.md covering the same skill appears correctly — just once, labeled (user).

To reproduce

1. Install a skill at ~/.claude/skills/my-skill/SKILL.md
2. Enable N plugins in ~/.claude/settings.json under enabledPlugins
3. Open the slash-command autocomplete (/) in any project
4. Observe my-skill appears N times (once per enabled plugin), all with the full SKILL.md description

Expected behavior

Each user-level skill appears exactly once in the autocomplete, regardless of how many plugins are enabled.

Actual behavior

The skill appears once per enabled plugin. With 5 plugins enabled, 5 identical entries appear. A matching ~/.claude/commands/my-skill.md adds a 6th entry labeled (user), for a total of 6 /my-skill entries in the autocomplete.

Evidence

Enabled plugins count matches duplicate count exactly:

enabledPlugins (5):
  - claude-code-setup@claude-plugins-official
  - skill-creator@claude-plugins-official
  - canopy-core-plugin@claude-canopy-marketplace
  - superpowers@claude-plugins-official
  - frontend-design@claude-plugins-official

→ 5 SKILL.md entries + 1 command entry = 6 total /collective-brain entries in autocomplete.

Filesystem search confirms there is only one SKILL.md file and one command file on disk — the duplication is entirely in the autocomplete rendering logic.

Environment

• Claude Code version: 2.1.168
• OS: macOS Darwin 24.6.0 arm64