feat: divide range larger than cache range limit for performance

[lucasfang]

Purpose

The changes ensure that individual ranges larger than the configured range_size_limit are automatically divided into smaller chunks before caching, preventing oversized cache entries that could negatively impact performance.

Tests

API and Format

Documentation

[Copilot]

Pull request overview

This pull request optimizes the byte range caching mechanism by introducing automatic range splitting and improving lock contention. The changes ensure that individual ranges larger than the configured range_size_limit are automatically divided into smaller chunks before caching, preventing oversized cache entries that could negatively impact performance.

Changes:

• Added logic to split byte ranges exceeding the cache range size limit into smaller chunks
• Optimized mutex lock timing in the caching mechanism to reduce lock contention and improve concurrency
• Updated test expectations to reflect the new range splitting behavior

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/paimon/common/utils/byte_range_combiner.cpp	Implements automatic splitting of byte ranges that exceed range_size_limit into smaller chunks before coalescing
src/paimon/common/utils/read_ahead_cache.cpp	Moves mutex lock acquisition to after sorting and async I/O initiation, reducing lock contention
src/paimon/common/utils/byte_range_combiner_test.cpp	Updates test expectations to validate the new range splitting behavior

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[lxy-9602]

+1