More colorful / themeable UI output

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Claude Code's output is very minimal in terms of color — most text renders as plain foreground white regardless of the terminal color scheme in use.
Changing the terminal theme has almost no visible effect on Claude Code's appearance.

Environment

• Windows Terminal → SSH → Debian → tmux
• Claude Code CLI

Proposed Solution

• Distinct colors for different message types (user input, assistant output, tool calls, errors)
• A way to configure or choose a color theme for Claude Code's UI
• Better use of the terminal's full 256/true color palette

Alternative Solutions

_No response_

Priority

Low - Nice to have

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_