wmux

A terminal multiplexer froze whenever I opened a diff pane on a non-git folder. I profiled the main process, found 92 percent of self-time in synchronous fs calls under a 2-second poll, and took one call from timeout to 0.7ms. Contribution, not authorship: 9 filed issues and 4 merged PRs (#135, #138, #153, #258) on diff-pane freezes, CLI timeouts, and agent-browser install discovery.