code: func (db *Database) GetStreamManager() (*StreamManager, error) {
  	if db.Header.FileHeaders != nil {
  		if db.Header.IsKdbx4() {
  			return NewStreamManager(
  				db.Content.InnerHeader.InnerRandomStreamID,
  				db.Content.InnerHeader.InnerRandomStreamKey,
  			)
  		}
  
  		return NewStreamManager(
  			db.Header.FileHeaders.InnerRandomStreamID,
  			db.Header.FileHeaders.ProtectedStreamKey,
  		)
  	}
  	return nil, nil
  }
docs: // GetStreamManager returns a StreamManager based on the db headers, or nil if the type is unsupported
  // Can be used to lock only certain entries instead of calling