Desktop: assistant text part is not rendered when the same message also contains tool calls

Description

In the desktop app, when a single assistant message contains both a text part and one or more tool-call parts, the UI renders the tool calls but omits the text part entirely. I only see the tool/shell invocations, never the assistant's written explanation.

Steps to reproduce

1. Open a session in the desktop app (Windows).
2. Have the assistant emit one message that contains a text part and a tool call (e.g. "Let me check the logs" followed by a bash tool call).
3. Observe: only the tool call is rendered, the text is missing.

Expected

The text part should be rendered, regardless of whether the same message also contains tool calls.

Workaround

If the assistant emits its text as a separate message with no tool calls, it renders normally. Short text-only messages always render fine.

Environment

• opencode desktop 1.18.30 (also reproduced on 1.18.31), Windows 11 Pro, build 26200
• renderer.log repeatedly shows:

[error] ResizeObserver loop completed with undelivered notifications.

Impact

Completely unusable for reading assistant explanations when tools are used in the same turn.