- Added early return when fetch_ranges is empty to optimize performance.
 - Replaced inline chunk data assignment with a call to `assign_dense_chunk` for cleaner code.

 - Introduced `RangeBase` to `BulkIterContext` for improved filter handling.
 - Implemented filter application in `BulkPartIter` to prune batches based on predicates.
 - Updated `SimpleFilterContext::new_opt` to be public for broader access.

 - Modified `BulkPart::read` to return `Option<BoxedBatchIterator>` to handle cases where no row groups are selected.
 - Added logic to return `None` when all row groups are filtered out.
 - Updated tests to handle the new return type and added a test case to verify behavior when no row groups match the pr

…et metadata and integrate it into BulkPartEncoder

 Change BulkPartEncoder row_group_size from Option to usize and update tests

…le iteration and refactor part reading

 • Introduce context module to encapsulate context for bulk memtable iteration.
 • Refactor BulkPart to use BulkIterContextRef for reading operations.
 • Remove redundant code in BulkPart by centralizing context creation and row group pruning logic in the new context module.
 • Create new file context.rs with structures and logic for handling iteration context.
 • Adjust part_reader.rs and row_group_reader.rs to reference the new BulkIterContextRef.

… implementations in memtable and parquet reader modules

 • Rename RowGroupReaderVirtual to RowGroupReaderContext for clarity.
 • Replace BulkPartVirt with direct usage of BulkIterContextRef in MemtableRowGroupReader.
 • Simplify MemtableRowGroupReaderBuilder by directly passing context instead of creating a BulkPartVirt instance.
 • Update RowGroupReaderBase to use context field instead of virt, reflecting the trait renaming and usage.
 • Modify FileRangeVirt to FileRangeContextRef and adjust implementations accordingly.

…on and remove unused code

 • Centralize creation of SerializedPageReader in RowGroupBase::column_reader method.
 • Remove unused RowGroupCachedReader and related code from MemtableRowGroupPageFetcher.
 • Eliminate redundant error handling for invalid column index in multiple places.