[BUG] Send button not appearing when text is entered (macOS desktop app)

Description

When text is typed in the input field, the send button does not appear — the microphone icon remains.
Messages can still be sent using the Enter key, but the send button never becomes visible.

Steps to Reproduce

1. Open Claude Code desktop app
2. Type text in the input field
3. Observe that the microphone icon remains instead of changing to a send button

Expected Behavior

The microphone icon should change to a send button when text is present in the input field.

Environment

• Platform: macOS (Darwin 25.2.0)
• Model: Opus 4.6 1M