refactor(aurora-portal): extract shared formatBytes utility with binary and decimal support

[mark-karnaukh-extern-sap]

Summary

Extracts duplicated inline formatBytes implementations from multiple components into a single shared utility supporting both binary (IEC) and decimal (SI) unit systems.

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Changes

New

• src/client/utils/formatBytes.ts — shared utility with formatBytes, formatBytesDecimal, formatBytesBinary

Updated

• SizeDisplay.tsx — replaced inline implementation with formatBytesDecimal
• ContainerListView.tsx — replaced inline implementation with shared utility
• List.tsx — replaced inline implementation with shared utility

Tests

• formatBytes.test.ts — new, full coverage of both unit systems, edge cases, decimals option
• SizeDisplay.test.tsx — updated expected values to match SI output
• ImageDetailsView.test.tsx — fixed size inputs to SI-round boundaries
• DeleteImageModal.test.tsx — fixed size: 1024 → size: 1000

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Notes

SizeDisplay uses formatBytesDecimal (SI) — appropriate since OpenStack APIs return raw byte counts, not binary-aligned values. Test fixtures that previously used binary boundaries (e.g. 1073741824, 1024) were updated to SI-round equivalents (e.g. 1000000000, 1000) to produce clean expected values.

Checklist

• I have performed a self-review of my code.
• I have commented my code, particularly in hard-to-understand areas.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• I have made corresponding changes to the documentation (if applicable).
• My changes generate no new warnings or errors.