Function build_reconciliation_column_metadata 

pub(crate) fn build_reconciliation_column_metadata(
    column_schemas: &[ColumnSchema],
    primary_key_indexes: &[usize],
    name_to_ids: &HashMap<String, u32>,
) -> Result<Vec<ColumnMetadata>>

Builds SyncColumns metadata with tags in the TableInfo primary-key order. Non-tag columns retain their schema positions.