feature: tmux-agents v1.3.0 agent ownership
I shipped v1.3.0 of tmux-agents to support the main → coordinator → worker chain: tmux-spawn --for <owner> lets main spawn a worker that belongs to and connects only to the coordinator, which introduces itself and sends the first task. The worker starts without a task, and depth counts from main so it can still spawn agents of its own. I also fixed messages to closed agent names landing in similarly named windows; missing names now fail, and agents are told to use the names tmux-peers shows now. Product decisions live one per file, with new regression tests for ownership and name matching.



