Companion (claudie): horizontal line artifact appears on hover

Description

When hovering over the claudie companion duck in the terminal footer, a horizontal line artifact appears across the terminal.

Steps to Reproduce

1. Open Claude Code CLI (v2.1.92)
2. Hover over the claudie companion in the bottom-right corner
3. A horizontal line appears spanning across the terminal

Expected Behavior

No horizontal line should appear on hover.

Actual Behavior

A horizontal line (likely from the speech bubble border or tail connector) renders as a visual artifact across the terminal.

Environment

• Claude Code v2.1.92
• macOS (Darwin 25.2.0)

Root Cause Analysis

The companion speech bubble component uses Ink Box with borderStyle: "round". When the companion is selected or reacting, a "─" tail connector character is rendered. This appears to cause the horizontal line artifact.