fix(storage): limit unclustered block selection in recluster compact phase

[zhyass]

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Summary

Recluster now caps the number of unclustered blocks selected for compaction per round, preventing the compact phase from becoming a bottleneck when tables have many unclustered segments.

• Added MAX_UNCLUSTERED_BLOCKS_PER_RECLUSTER (1000) as the upper bound, further capped by compact_max_block_selection setting
• Recluster select_segments now tracks unclustered_block_num and breaks early once the limit is reached, allowing incremental progress across multiple invocations

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):

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