/voice command shows 'Unknown skill: voice' despite startup banner advertising it

Description

Claude Code v2.1.76 displays this on startup:

✻ Voice mode is now available · /voice to enable

But typing /voice at the prompt returns:

❯ Unknown skill: voice

Steps to reproduce

1. Launch claude (v2.1.76)
2. Observe startup banner mentions /voice
3. Type /voice
4. Get "Unknown skill: voice"

Environment

• Claude Code v2.1.76
• macOS (Darwin 25.2.0)
• Claude Max subscription

Expected behavior

/voice should activate voice mode as advertised in the startup banner.