Add column-aware scan feature

[panarch]

Summary

• add scan_data_with_columns method to Store trait with default implementation
• test default method via memory storage integration test
• implement optimized projection for Parquet storage
• add Parquet integration test using new method

Testing

• cargo clippy --all-targets -- -D warnings
• cargo fmt --all

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https://chatgpt.com/codex/tasks/task_e_6862225bceb0832aae028b4b5082ca86