/mcp TUI locks terminal — no keys respond, must kill shell

Bug

Running /mcp in the Claude Code CLI hangs the terminal immediately. The interactive picker normally lets me arrow up/down between MCP servers, but in this state no input works — arrow keys, Esc, Ctrl+C, nothing. Only recourse is killing the shell.

Environment

• Claude Code: 2.1.118
• macOS: 26.5 (build 25F5042g)
• Shell: zsh

MCP setup

• ~16 MCP servers configured: 6 healthy local/SSE, ~10 organization-managed claude.ai * connectors that show "! Needs authentication" or "✗ Failed to connect" in claude mcp list.
• The org-managed connectors cannot be removed from the CLI (claude mcp remove reports "no server found") and appear to be greyed-out / non-removable in claude.ai → Settings → Connectors, presumably because they're pushed by an org admin.

Steps to reproduce

1. Have several claude.ai * connectors in unauthenticated / failed state (visible in claude mcp list).
2. Launch claude.
3. Type /mcp.

Expected

• TUI renders, arrow keys navigate the server list, Esc exits.

Actual

• TUI does not render usable state. All keyboard input is swallowed. Must kill the terminal process to recover.

Attempted workarounds

• export MCP_TIMEOUT=3000 — no effect (it controls server startup timeout, not the TUI).
• Removing the one local OAuth-pending server (sentry) — no effect; the org-managed claude.ai Sentry remains and still hangs /mcp.

Suggested fixes

• /mcp should be cancellable (Esc / Ctrl+C should always work).
• /mcp should render with a timeout per server rather than blocking the entire TUI until all servers respond.
• Provide a way to opt out of org-pushed connectors locally (~/.claude/settings.json flag or per-server disable).