/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.