fix(query): fix variant cast to number

[b41sh]

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Summary

This PR allows the variant value of floating-point numbers to be cast as integers, and floating-point numbers will be converted to integers by rounding

for example

select to_int64(parse_json('123.0')), to_int64(parse_json('999.9'));
╭───────────────────────────────────────────────────────────────╮
│ to_int64(parse_json('123.0')) │ to_int64(parse_json('999.9')) │
│             UInt8             │             UInt16            │
├───────────────────────────────┼───────────────────────────────┤
│                           123 │                          1000 │
╰───────────────────────────────────────────────────────────────╯
1 row read in 0.047 sec. Processed 1 row, 1 B (21.28 rows/s, 21 B/s)

• 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