fix: [DO NOT MERGE]ensure additionalStatsMeta.location is always populated in snapshots

[zhyass]

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Summary

This commit ensures that the location field in AdditionalStatsMeta is always set (never None) when creating snapshots. Previously, location could be None, causing compatibility issues during schema evolution. By providing a default placeholder (("", 0)), this change facilitates smoother upgrades and backward compatibility for downstream consumers.

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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Docker Image for PR

• tag: pr-18629-43109ec-1756372681

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