Expose public async bloom filter reader (metadata + `AsyncFileReader`)

**Is your feature request related to a problem or challenge? Please describe what you are trying to do.**

I'm integrating Parquet bloom filters into an async pruning pipeline and found a gap in the public API.

For current situation,

- There is a sync API:
`Sbbf::read_from_column_chunk(column_meta, reader)`
- There is an async method, but only on the async Arrow builder:
`ParquetRecordBatchStreamBuilder::get_row_group_column_bloom_filter(...)`
- The helper used internally to parse bloom filter headers is `pub(crate)`:
`chunk_read_bloom_filter_header_and_offset` (in `parquet::bloom_filter`)

If parquet crate only has `ParquetMetaData` + an `AsyncFileReader`, downstream applications can't read bloom filters without re‑implementing Parquet bloom header parsing.

This blocks async metadata‑only pruning libraries (like me) from using bloom filters safely and efficiently.

**Describe the solution you'd like**

Expose a public async bloom reader that mirrors the sync API:

```rust
pub async fn read_bloom_filter_async(
column_meta: &ColumnChunkMetaData,
reader: &mut R
) -> Result>;
```

This would:

- keep internal header parsing private
- allow async pruning without coupling to Arrow builder
- avoid duplicate parsing logic in downstream crates
- be backwards compatible (pure API addition)

*Alternative*
Make `chunk_read_bloom_filter_header_and_offset` public, but this is a low‑level parsing helper and would bake in more implementation detail.

Start in parquet::bloom_filter by reading chunk_read_bloom_filter_header_and_offset, then compare Sbbf::read_from_column_chunk with ParquetRecordBatchStreamBuilder::get_row_group_column_bloom_filter and the AsyncFileReader interface. Done means a public async reader accepts ColumnChunkMetaData and an AsyncFileReader, returns the requested bloom filter result, and keeps internal header parsing private.

Written by the indexing model from the issue text.