Feature request: Customizable display names in CLI output

Summary

Allow users to configure display names that appear in CLI output, such as changing "User answered Claude's questions" to custom names.

Use Case

Users who have established a working relationship with Claude (including naming their instance) would benefit from seeing personalized names in the interface rather than generic "User" and "Claude" references.

Proposed Solution

A display_name setting in settings.json or similar:

{
  "display_names": {
    "user": "Luke",
    "assistant": "Vera"
  }
}

This would affect UI strings like:

• "User answered Claude's questions" → "Luke answered Vera's questions"
• Other status messages that reference user/assistant

Additional Context

This is a low-priority quality-of-life feature, but it would make the tool feel more personal for users who use it extensively as a collaborative partner rather than just a utility.