Issue 35310 block folder delete when not empty

[riccardoruocco]

Proposed Changes

• add a config flag to block folder deletion when the folder or one of its descendants is not empty
• keep the default behavior unchanged when the flag is disabled
• update the user-facing i18n message

Checklist

• Tests
• Translations
• Security Implications Contemplated (add notes if applicable)

Additional Info

This change is intentionally minimal and scoped to the existing folder delete action in the UI flow. It does not change backend delete APIs.

Screenshots

Updated

[riccardoruocco]

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