Fix control pipe accept loop: create instances only after a client connects; CLI force-update never touches the service log file

internal/control/control_windows.go

@@ -77,18 +77,16 @@ func Serve(ctx context.Context, h Handler, log *slog.Logger) error {
 				log.Warn("control channel stopped", "err", err)
 				return
 			}
-			go func() {
-				// Blocks until a client connects; on process exit the
-				// handle goes away with everything else. A client that
-				// raced us and connected between CreateNamedPipe and
-				// ConnectNamedPipe reports ERROR_PIPE_CONNECTED — that is
-				// a success, not a failure.
-				if err := windows.ConnectNamedPipe(pipe, nil); err != nil && err != errnoPipeConnected {
-					windows.CloseHandle(pipe)
-					return
-				}
-				serveConn(&pipeConn{f: os.NewFile(uintptr(pipe), pipePath), h: pipe}, h)
-			}()
+			// Blocks until a client connects — only then is the next
+			// instance created, so instances are not burned without
+			// clients. ERROR_PIPE_CONNECTED means the client raced us
+			// and connected before the call: that is a success. Process
+			// exit reaps the blocked call on shutdown.
+			if err := windows.ConnectNamedPipe(pipe, nil); err != nil && err != errnoPipeConnected {
+				windows.CloseHandle(pipe)
+				continue
+			}
+			go serveConn(&pipeConn{f: os.NewFile(uintptr(pipe), pipePath), h: pipe}, h)
 		}
 	}()
 	return nil