/mcp dialog immediately dismissed without displaying

Description

The /mcp slash command dialog renders as a blank/empty screen. No UI elements (server list, configuration options, etc.) are visible. The only way to exit is pressing Escape, which then outputs "MCP dialog dismissed".

Steps to Reproduce

1. Open Claude Code CLI
2. Type /mcp and press Enter
3. Screen changes but no dialog content is rendered — it appears blank
4. Press Escape to exit — output shows "MCP dialog dismissed"

Expected Behavior

The MCP server configuration dialog should render with visible UI elements allowing the user to view and manage MCP server connections.

Actual Behavior

The dialog opens but renders nothing — the screen is blank/empty with no visible UI. User must press Escape to return.

Environment

• OS: macOS (Darwin 25.2.0)
• Shell: zsh
• Claude Code model: claude-opus-4-6