CI / flake (pull_request) Successful in 3m35s
kube-tmux is not in nixpkgs, so add the upstream repo as a flake = false
input and reference ${inputs.kube-tmux}/kube.tmux directly. The script is now
always in the store, so the previous $HOME/code/kube-tmux existence guard is
removed and the tmux status line no longer depends on a manual checkout.
Refs #50