refactor(web): restore DASDFormatProgress with API v2 event model

[dgdavid]

As a follow up of #3143, restores the DASD format progress by adapting DASDFormatProgress to the new API v2 event model, using DASDFormatChanged websocket events to drive progress state and only rendering when formatting is actually active.

To support injecting the per-device progress details into the existing backdrop overlay, ProgressBackdrop was extended with an extraContent prop, which can be used by pages to inject any extra content of their convenience to the progress overlay.

This PR was also taken as an opportunity to improve the readability of the progress overlay, on hold since #2947, by wrapping its content in a Card layout, which provides a clear visual container, structured spacing, and scrollable content for long step messages.

A waitingLabel prop was added as another minor improvement to let consumers override the default "Refreshing data..." message shown while queries finish refetching.

Note: screenshots below were taking using fake data. Thus, do not pay attention to coherence to rendered texts, but to how they are rendered. Only "Formatting devices progress" is a text to be reviewe, check https://github.com/agama-project/agama/pull/3230/changes#diff-3dbadc1060b5324017efc04eb74b73781eaa8d72e8ff7c3a2d934adee4c315f7R101

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Related to https://trello.com/c/xdvueNDg/, private link.

[joseivanlopez]

LGTM