AskUserQuestion UI not rendered when called after Skill tool invocation

Bug Description

AskUserQuestion tool sometimes fails to render the question UI. Instead of showing the question with options, it immediately returns "User answered Claude's questions:" with an empty answer.

Steps to Reproduce

1. Create a skill (slash command) that internally calls AskUserQuestion
2. Invoke the skill via /skill-name with arguments
3. The skill processes arguments and calls AskUserQuestion with options
4. Expected: UI displays the question with selectable options
5. Actual: No question UI shown, empty answer returned immediately

Example Call

{
  "questions": [{
    "question": "To be or not to be?",
    "header": "Hamlet",
    "options": [
      {"label": "To be", "description": "Choose existence"},
      {"label": "Not to be", "description": "Choose non-existence"}
    ],
    "multiSelect": false
  }]
}

Screenshot

The UI shows:

● User answered Claude's questions:
  └

No question text, no options displayed. Answer is empty.

Additional Context

• The bug appears to occur specifically when AskUserQuestion is called shortly after a Skill tool invocation in the same conversation turn
• A subsequent AskUserQuestion call (without Skill context) in the next turn rendered correctly
• This may be related to the timing/sequencing of tool calls after skill expansion
• Platform: macOS (Darwin 24.6.0)
• Claude Code CLI