feat(cli): classify every provisioning failure with stable codes

cmd/cli/prog_log.go

@@ -31,3 +31,12 @@ func (p *prog) Error() *ctrld.LogEvent {
 func (p *prog) Notice() *ctrld.LogEvent {
 	return p.logger.Load().Notice()
 }
+
+// notifyExitToLogServer closes this run's connection to the HTTP log server,
+// so a waiting "ctrld start" is not left waiting on it after this process
+// exits. A nil connection (log server never started) is a no-op.
+func (p *prog) notifyExitToLogServer() {
+	if p.logConn != nil {
+		_ = p.logConn.Close()
+	}
+}