Cannot select/copy text from user messages in chat interface

Description:
User messages (displayed in yellow/orange boxes) are not selectable with mouse cursor, preventing copy-paste functionality. Agent responses can be selected and copied normally.

Expected behavior:
All text in the chat window should be selectable and copyable for easy reference and re-use.

Environment:

• OS: Windows
• Claude Code CLI

Steps to reproduce:

1. Send a message in the Claude Code chat
2. Try to highlight/select the text in your own message (yellow/orange box)
3. Text selection does not work

Actual behavior:
User cannot select or copy their own messages from the chat window.

Impact:
This is an accessibility and usability issue that prevents users from easily referencing or reusing their previous messages.