public int size() {
        return document.size();
    }
Use {@link BsonDocument} instead of {@link Document} because {@link Document} will be
converted to {@link BsonDocument} by mongo-java-driver finally, which is a huge waste of
system resources because both documents are heavy
turms-server-common/src/main/java/im/turms/server/common/storage/mongo/operation/option/BaseBson.java