Take the chat client's port from Run's caller (closes #4)

The test that runs the whole bot started its stand-in chat client on
5225, the port a real simplex-chat uses, so on a machine where one
listens there the test would have sent it the bot's set-up commands.
Run now takes the chat client's port: the run command passes
bot.ChatPort (5225), and the test a port it found free.

Model: opus-5-5

internal/cli/run.go

@@ -45,7 +45,7 @@ func run(ctx context.Context, version string) error {
 	ctx, stop := signal.NotifyContext(ctx, syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 
-	err = bot.Run(ctx, log, cfg)
+	err = bot.Run(ctx, log, cfg, bot.ChatPort)
 	if err != nil {
 		log.Error("stopped", "error", err)