"Copied to clipboard" notification is misleading when selecting text without Shift key

### Describe the bug

Environment:

• OS: macOS 26.5.2 (Build 25F84)
• Terminal: Ghostty 1.3.1
• Copilot CLI version: 1.0.68

When I select text with mouse, I get message "Copied to clipboard" however, when right click to pate, it states again "Copied to clipboard", the 2nd right click pastes instead of the first.

Workaround: Use Shift + select to copy text reliably.

### Affected version

GitHub Copilot CLI 1.0.68.

### Steps to reproduce the behavior

1. Mark text with mouse
2. Right-click

### Expected behavior

Text is pasted

### Additional context

_No response_

Reproduce the behavior with GitHub Copilot CLI 1.0.68 on macOS 26.5.2 using Ghostty 1.3.1: select text with the mouse and right-click once. Trace the selection and clipboard handling from that interaction; done means the first right-click pastes the selected text instead of showing another "Copied to clipboard" notification.

Written by the indexing model from the issue text.