chore(query): improve decimal aggregate state

[sundy-li]

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Summary

https://blog.rust-lang.org/2024/03/30/i128-layout-update.html

align of i128 has been changed from 8 to 16 bytes which increases the allocated state size.

This pr make decimal state stored as u64 arrays which keep the align as 8 bytes.

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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This change is