terminal-setup fails to detect Windows Terminal

Bug

/terminal-setup reports Terminal setup cannot be run from windows-terminal even when running inside Windows Terminal.

Root Cause

Windows Terminal does not set TERM_PROGRAM. It uses WT_SESSION and WT_PROFILE_ID instead. The detection logic likely checks TERM_PROGRAM but not the Windows Terminal-specific env vars.

Environment

• Windows 10 Pro for Workstations 10.0.19045
• Windows Terminal (WT_SESSION is set, WT_PROFILE_ID is set)
• TERM_PROGRAM is empty
• TERM=xterm-256color
• Claude Code CLI (claude-opus-4-6)

Expected

/terminal-setup should detect Windows Terminal via WT_SESSION and proceed with configuration.

Actual

Reports it cannot be run from windows-terminal and suggests switching to Windows Terminal (which is already in use).