feat(list): Add ability to sort using flat attributes (sort_by and sort_order)

[raulb]

What kind of change does this PR introduce?

1. Ability to sort using flat formats:

storage.list('path', { sort_by: 'name', sort_order: 'desc' })

2. Clean up unused code and adds a storage client to use in tests.

What is the current behavior?

storage.list('path', { sortBy: { column: 'name', order: 'desc' } })

What is the new behavior?

Both old and new behavior are compatible.

Additional context

To be used on https://github.com/supabase/infrastructure/pull/25305.

Question

Need some insights on how to update https://supabase.com/docs/reference/javascript/storage-from-list once this ships and it's part of a new release.

[github-actions]

🚀 Preview Release Status

false

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_{Last updated: 2025-09-01T07:24:13Z}

[raulb]

This is not needed. Happy to open a PR with this branch which contains the code left after this commit as you might find it useful for testing. Please, let me know!