fix(query): fix cast nested types cause panic

[b41sh]

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Summary

ArrayColumn only intercepts offsets when executing the slice function without modifying the underlying values, resulting in a panic when the length of the values is not matched with the offsets when using values directly. this PR changes the fields values and offsets of ArrayColumn from public to private, the values inside ArrayColumn can be used by calling underlying_column and underlying_offsets to avoid getting incorrect values.

By the way, the set variable syntax has been changed to allow query with parenthesis to be executed correctly.

• fixes: bug: cast nested type cause panic #17620

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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