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Summary

Ensure snapshot timestamp is not behind the table’s least visible time when updating table metadata

This PR adds a safety check during table metadata updates to verify that the snapshot timestamp is greater than or equal to the table’s least visible time (LVT).
This prevents newly referenced or committed snapshots from falling behind the vacuum boundary and being incorrectly reclaimed while vacuum is running.

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):

This change is