Introduces a new 'storage_class' configuration option for S3 providers. Users can now specify the desired storage class (e.g., Standard, GLACIER, DEEP_ARCHIVE) for objects uploaded to S3-compatible services like AWS S3 and Tencent COS.
The input storage class string is normalized to match AWS SDK constants, supporting various common aliases. If an unknown storage class is provided, it will be used as a raw value with a warning. This enhancement provides greater control over storage costs and data access patterns.