feat: support prefetch for orc

[lucasfang]

Purpose

Support prefetch for ORC , and wiring a read-ahead cache into the existing PrefetchFileBatchReaderImpl. Introduce a shared ReadAheadCache + CacheInputStream to serve prefetched byte ranges to parallel readers.

API and Format

PrefetchFileBatchReader:
virtual Result<std::vector<std::pair<uint64_t, uint64_t>>> PreBufferRange();
ReadContext:
bool EnablePrefetchCache() const and const CacheConfig& GetCacheConfig() const
ReadContextBuilder:
ReadContextBuilder& WithCacheConfig(const CacheConfig& config);
ReadContextBuilder& EnablePrefetchCache(bool enabled);

[Copilot]

Pull request overview

Adds ORC support to the prefetch path by introducing ORC-aware read-range generation and byte-range prebuffering, and wiring a read-ahead cache into the existing PrefetchFileBatchReaderImpl.

Changes:

• Add ORC ReadRangeGenerator and OrcReaderWrapper to support row-range generation and ORC prebuffer range hints.
• Introduce a shared ReadAheadCache + CacheInputStream to serve prefetched byte ranges to parallel readers.
• Extend prefetch/caching controls via ReadContext/builder and expand integration/unit tests to cover ORC prefetch scenarios.

Reviewed changes

Copilot reviewed 30 out of 30 changed files in this pull request and generated 17 comments.

Show a summary per file

File	Description
test/inte/scan_and_read_inte_test.cpp	Adds ORC prefetch=true parameterization for integration coverage.
test/inte/read_inte_with_index_test.cpp	Adds ORC prefetch=true parameterization for integration coverage.
test/inte/read_inte_test.cpp	Expands ORC test params to include prefetch combinations.
src/paimon/format/orc/read_range_generator_test.cpp	New unit tests for ORC row-range generation / thresholds.
src/paimon/format/orc/read_range_generator.h	Declares ORC row-range generator API.
src/paimon/format/orc/read_range_generator.cpp	Implements ORC row-range generation and prefetch decision logic.
src/paimon/format/orc/orc_reader_wrapper_test.cpp	New unit test for wrapper row position tracking.
src/paimon/format/orc/orc_reader_wrapper.h	Introduces wrapper to expose GetNextRowToRead and prebuffer hints.
src/paimon/format/orc/orc_reader_wrapper.cpp	Implements wrapper seek/schema/next-batch logic.
src/paimon/format/orc/orc_input_stream_impl.h	Adds async-read tracking fields.
src/paimon/format/orc/orc_input_stream_impl.cpp	Implements ORC async read via underlying InputStream::ReadAsync.
src/paimon/format/orc/orc_format_defs.h	Adds ORC prefetch threshold-related constants.
src/paimon/format/orc/orc_file_batch_reader_test.cpp	Updates tests for new row reader options signature/column id capture.
src/paimon/format/orc/orc_file_batch_reader.h	Switches ORC reader to PrefetchFileBatchReader + prefetch APIs.
src/paimon/format/orc/orc_file_batch_reader.cpp	Wires ORC reader wrapper + read-range generation into batch reader.
src/paimon/format/orc/CMakeLists.txt	Adds new ORC sources and tests to the build.
src/paimon/core/operation/read_context.cpp	Adds prefetch-cache options into read context/builder plumbing.
src/paimon/core/operation/internal_read_context.h	Exposes prefetch-cache settings to internal read pipeline.
src/paimon/core/operation/abstract_split_read.cpp	Enables prefetch path for ORC and passes cache config into prefetch reader.
src/paimon/core/deletionvectors/apply_deletion_vector_batch_reader_test.cpp	Updates prefetch reader construction to include cache params.
src/paimon/common/utils/byte_range_combiner.h	Adjusts combiner API/visibility after refactor.
src/paimon/common/utils/byte_range_combiner.cpp	Refactors coalescing implementation into CoalesceByteRanges.
src/paimon/common/reader/prefetch_file_batch_reader_impl_test.cpp	Updates tests for new prefetch reader ctor and adds ORC format where available.
src/paimon/common/reader/prefetch_file_batch_reader_impl.h	Extends Create/ctor to accept cache config + cache instance.
src/paimon/common/reader/prefetch_file_batch_reader_impl.cpp	Creates shared read-ahead cache and initializes it using PreBufferRange().
src/paimon/common/fs/cache_input_stream.h	New InputStream wrapper serving reads from ReadAheadCache when possible.
src/paimon/common/file_index/bitmap/apply_bitmap_index_batch_reader_test.cpp	Updates prefetch reader construction to include cache params.
include/paimon/reader/prefetch_file_batch_reader.h	Adds PreBufferRange() API for byte-range prefetch hints.
include/paimon/read_context.h	Adds builder APIs and getters for enabling/configuring prefetch cache.
cmake_modules/orc.diff	Patches upstream ORC to expose preBufferRange(...) and reuse it in preBuffer.

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[lxy-9602]

+1