AskUserQuestion: option description not shown when preview is present

Bug

When an AskUserQuestion option includes a preview field, the description field is not rendered in the UI.

Steps to reproduce

1. Call AskUserQuestion with options that have both description and preview fields:

{
  "questions": [{
    "question": "A",
    "header": "B",
    "options": [
      { "label": "C", "description": "D", "preview": "E" },
      { "label": "F", "description": "G", "preview": "H" }
    ],
    "multiSelect": false
  }]
}

1. Only label and preview are rendered. description is silently dropped.

Without preview (working correctly)

When preview is omitted, description renders correctly below each option label.

{
  "options": [
    { "label": "C", "description": "D" },
    { "label": "F", "description": "G" }
  ]
}

Expected behavior

Both description and preview should be visible, since the schema accepts both fields simultaneously. If description is intentionally hidden in preview mode, the tool schema docs should say so explicitly — currently they only mention the layout switches to side-by-side, not that descriptions are dropped.

Screenshots

With preview — description missing

!with-preview

Without preview — description visible

!without-preview

Environment

• Claude Code CLI (macOS)
• Tested 2026-04-08