Select-all checkbox for object operations inside swift containers in Horizon

Summary
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This blueprint aims to implement a batch select option to Horizon's Object Storage module.

Motivation
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Horizon Dashboard should maintain operation consistency between modules and should promote a high usability standard for users of all niches.

Description
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It has been noted that Horizon has a series of usability issues. One of them regards the usability of the container and object management in the Object Storage module in Horizon.

It is noted that inside containers you can select multiple objects to operate on (delete basically), but you don't have a 'select-all' checkbox like those present in the Images module and alike and neither you can hold shift and select multiple objects. Hence you need to select manually all the objects in a container in order to delete them all through horizon.

To keep consistency and usability Horizon should implement the select-all checkbox for the Object Storage module. This option would also improve usability in the case where a user wants to delete a whole container through Horizon (as it is now, the user must first delete all the objects and folders before deleting the container).

UX
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The only aspect of the UX would be the addition of a checkbox that selects all elements inside a container.

Wireframes, Mocks, Videos and UI Markup
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N/A

Testing
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N/A

Outside Dependencies
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N/A

Requirements Update Required
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N/A

Doc Impact
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N/A