enable xattr capture by default (#18911)

- healing must not set the write xattr
  because that is the job of active healing
  to update. what we need to preserve is
  permanent deletes.

- remove older env for drive monitoring and
  enable it accordingly, as a global value.

cmd/globals.go

@@ -56,6 +56,7 @@ import (
 	"github.com/minio/minio/internal/event"
 	"github.com/minio/minio/internal/pubsub"
 	"github.com/minio/pkg/v2/certs"
+	"github.com/minio/pkg/v2/env"
 	xnet "github.com/minio/pkg/v2/net"
 )
 
@@ -413,6 +414,8 @@ var (
 	globalLocalDrives   []StorageAPI
 	globalLocalDrivesMu sync.RWMutex
 
+	globalDriveMonitoring = env.Get("_MINIO_DRIVE_ACTIVE_MONITORING", config.EnableOn) == config.EnableOn
+
 	// Is MINIO_CI_CD set?
 	globalIsCICD bool