Feature: Expose session rename/color as programmable API

Use Case

When running multiple Claude Code sessions as a pool of dedicated experts (e.g., one session per ticket, one per domain), it would be valuable for sessions to auto-name and color themselves based on the work they're assigned. Today, /rename and /color are interactive-only CLI commands — there's no way for hooks, skills, or tools to invoke them programmatically.

Proposed Solution

Expose session metadata (name, color) through one or more of:

1. A writable metadata file (e.g., ~/.claude/sessions/{id}/meta.json) that the TUI watches for changes
2. CLI flags (claude --session-name "botboy" --session-color yellow)
3. A tool or built-in function that Claude itself can call (e.g., a RenameSession tool)
4. Hook support — allow hooks to emit special directives that the TUI interprets (e.g., echo "::set-session-name::botboy")

Any of these would enable automation patterns like:

• A /ticket skill that renames the session to the ticket ID when work begins
• An agent pool manager that color-codes sessions by domain (red = infra, blue = frontend, etc.)
• Automatic session naming based on the git branch being worked on

Current Workaround

The user must manually type /rename and /color after each task assignment. This breaks the flow when orchestrating multiple concurrent sessions.

Environment

• Claude Code CLI
• Multiple concurrent sessions via Zellij/tmux
• Skills and hooks configured for ticket workflow automation