Add strong warning before permanent item deletion (#5044)

[guillermo-escire]

References

Fixes #5044

Description

Adds a stronger confirmation dialog before permanently deleting an item, warning administrators about irreversible deletion and potential impact on citations and external references.

Instructions for Reviewers

This PR improves the deletion workflow for items by adding a stronger confirmation dialog before permanent deletion.

List of changes in this PR:

• Added a modal-based confirmation dialog before item deletion.
• Introduced new i18n translation keys for the deletion warning messages.
• Displayed a clear warning informing administrators that deletion is permanent and may break external references and scholarly citations.

How to test:

1. Log in as an administrator.
2. Navigate to any item and open the edit page.
3. Click the Delete action.
4. Verify that a confirmation modal appears with a strong warning message.
5. Confirm that deletion only proceeds after explicitly confirming in the dialog.

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