feat(muxterm): PTY pool with attach, resize, cleanup

muxterm/ws_stub.go

@@ -0,0 +1,8 @@
+package main
+
+import "net/http"
+
+// HandleWebSocket is a placeholder that will be replaced in a later task.
+func HandleWebSocket(pool *Pool, secret string, w http.ResponseWriter, r *http.Request) {
+	http.Error(w, "not implemented", http.StatusNotImplemented)
+}