chore(query): Set the default value of enable_experimental_virtual_column as true

[b41sh]

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Summary

This PR set the default value of enable_experimental_virtual_column as true. Generate virtual columns by default for variant type data to optimize the performance of some queries and reduce OOM

• fixes: #[Link the issue here]

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 

[github-actions]

🤖 Smart Auto-retry Analysis (Retry 5)

Workflow: 17133638848

📊 Summary

• Total Jobs: 22
• Failed Jobs: 2
• Retryable: 0
• Code Issues: 2

❌ NO RETRY NEEDED

All failures appear to be code/test issues requiring manual fixes.

🔍 Job Details

• ❌ linux / build (x86_64, X64): Not retryable (Code/Test)
• ❌ linux / test_unit: Not retryable (Code/Test)

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