feat(java): add builder-style scalar index params

[wojiaodoubao]

Introduce some builder classes to make creating scalar index easy. For example.

  ScalarIndexParams params = BTreeIndexParams.builder()
      .zoneSize(2048)
      .build();

  IndexParams indexParams = IndexParams.builder().setScalarIndexParams(scalarParams).build();

   // Create BTree index on 'id' column
   dataset.createIndex(
       Collections.singletonList("id"),
       IndexType.BTREE,
       Optional.of("btree_id_index"),
       indexParams,
       true);