Regression: Win+H (Windows Voice Typing) no longer works in the CLI input box

### Describe the bug

Regression: Win+H (Windows Voice Typing) no longer works in the CLI input box — broke with the v1.0.61 input restyling.

Repro:

1. Launch copilot (Windows 11, Windows Terminal)
2. Focus the input prompt
3. Press Win+H
4. Get error: "To use voice typing, select a text box then try again"

Confirmed not a Windows-side issue: Win+H works correctly in Notepad in the same session.

Used to work in prior versions. The 1.0.61 changelog notes "styled inputs… borders, headers" — the new input frame appears to no longer expose itself to Windows as a standard editable control, so voice typing (and likely other IME / accessibility tools) cannot target it.

Impact: blocks dictation as an input method, which is meaningful for long prompts.

Version: 1.0.61

### Affected version

_No response_

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

Start by reproducing the issue on Windows 11 in Windows Terminal with version 1.0.61, then compare the input behavior with a prior version and with Notepad. Focus on the input restyling noted in the v1.0.61 changelog; done means Win+H can target the CLI input box again without regressing normal prompt entry.

索引モデルが issue の本文から書いたものです。