chore: change parquet_fast_read_bytes setting from 0 to 16MB

[BohuTANG]

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Summary

When copying from the Parquet stage, we default to reading metadata each time, which is not efficient for small Parquet files (less than 16MB) due to the cost of reading metadata.

This PR sets parquet_fast_read_bytes default value to 16MB, meaning if a parquet file is less than 16MB, we won't read the metadata; instead, we'll read the entire file.

Relate Code:
1.

databend/src/query/storages/parquet/src/parquet_rs/parquet_table/partition.rs

Lines 79 to 92 in c2e3ee6

	let fast_read_bytes = ctx.get_settings().get_parquet_fast_read_bytes()?;
	let mut large_files = vec![];
	let mut large_file_indices = vec![];
	let mut small_file_indices = vec![];
	let mut small_files = vec![];
	for (index, (location, size)) in file_locations.into_iter().enumerate() {
	if size > fast_read_bytes {
	large_files.push((location, size));
	large_file_indices.push(index);
	} else {
	small_files.push((location, size));
	small_file_indices.push(index);
	}
	}

databend/src/query/storages/parquet/src/parquet_rs/parquet_table/partition.rs

Lines 136 to 155 in c2e3ee6

	let (mut stats, mut partitions) = if parquet_metas.is_empty() {
	self.read_and_prune_metas_in_parallel(
	ctx,
	large_files,
	pruner,
	columns_to_read,
	Arc::new(topk),
	copy_status,
	)
	.await?
	} else {
	prune_metas_in_parallel(
	ctx,
	&parquet_metas,
	large_file_indices,
	pruner,
	columns_to_read,
	Arc::new(topk),
	copy_status,
	)

• Fixes #[Link the issue here]

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

---

This change is 

[BohuTANG]

The default value for parquet_fast_read_bytes is 16MB, so there's no need to configure it. CC @yufan022

[yufan022]

The default value for parquet_fast_read_bytes is 16MB, so there's no need to configure it. CC @yufan022

Copy that. Our current setting is 1073741824.