[Kernel][Type Widening] 7/ Collect TypeChanges to FieldMetadata

[emkornfield]

🥞 Stacked PR

Use this link to review incremental changes.

• stack/tw_type_changes [Files changed]
  • stack/tw_type_changes_to_field_metadata [Files changed]
    • stack/tw_type_changes_to_field_metadata_impl [Files changed]
      • stack/tw_serde_refactor [Files changed]
        • stack/add_type_change_parsing [Files changed]
          • stack/tw_upgrade_downgrade [Files changed]

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Which Delta project/connector is this regarding?

• [ ] Spark
• [ ] Standalone
• [ ] Flink
• [x] Kernel
• [ ] Other (fill in here)

Description

This PR adds logic to collect type changes from leaf fields and appropriately populate FieldMetadata on the nearest StructField, following the pattern already established by collations. Because this is on the StructField it means extra work is performed for nested maps/elements, fixing this is outside the scope of the PR>

How was this patch tested?

New unit tests.

Does this PR introduce any user-facing changes?