/mcp interactive menu: arrow keys, j/k, and Tab/Shift-Tab navigation broken

## Description

The `/mcp` command's interactive menu does not respond to any keyboard navigation method:
- Arrow keys (up/down) — no effect
- j/k — no effect
- Tab / Shift-Tab — no effect

This appears to be a recurring regression — navigation worked in a previous version and has broken again.

## Environment

- **Claude Code version:** 2.1.270
- **Platform:** macOS (Darwin 25.6.0)
- **Terminal:** iTerm.app (xterm-256color)

## Steps to Reproduce

1. Run `/mcp` in Claude Code CLI
2. An interactive menu appears with choices
3. Attempt to navigate with arrow keys, j/k, or Tab/Shift-Tab
4. None of the keys move the selection

## Expected Behavior

Arrow keys (and ideally j/k or Tab) should move the selection highlight between menu items.