Copilot CLI output truncation when running shell command ! aspire run – Aspire Dashboard URL inconsistently missing

### Describe the bug

When running !aspire run (using ! to execute the command directly in the shell) inside Copilot CLI, the command output is inconsistently displayed. In some executions, important trailing lines; especially the Aspire Dashboard URL are missing from the displayed output.
This behavior is inconsistent: the same command in the same repository sometimes shows the full output (including the dashboard URL) and sometimes truncates it early. Because the command is executed directly in the shell via !, this appears to be an output rendering or streaming issue within Copilot CLI rather than an Aspire CLI issue.
When the dashboard URL is not shown, I have to open VS Code and retrieve it via the Aspire extension, which breaks the CLI-first workflow.

### Affected version

GitHub Copilot CLI 1.0.12

### Steps to reproduce the behavior

1. Open Copilot CLI
2. Navigate to an Aspire-based project
3. !aspire run
4. Stop and re-run the command multiple times

### Expected behavior

The full shell output from aspire run is consistently displayed, including:

AppHost project path
Aspire Dashboard URL
Logs path

### Additional context

首先，在 Copilot CLI 1.0.12 中透過重複執行 !aspire run 命令重現問題，然後追蹤 shell 命令輸出的呈現或串流路徑。比較存在 Aspire Dashboard URL 的執行結果與缺少尾端輸出的執行結果；當完整輸出始終包含 AppHost 路徑、儀表板 URL 和 logs 路徑時，即表示完成。

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