af8ee1609b
tmux-direct as default-terminal desyncs zsh's line redraw on some terminals (iTerm2: duplicated characters on Tab, stray newlines). Switch to the standard tmux-256color and advertise truecolor per outer terminal via terminal-features (add xterm-256color:RGB alongside the foot ones). Also add a NO_TMUX escape hatch to the auto-start guard, so `NO_TMUX=1 <terminal>` opens a bare shell. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>