This webhook is triggered when a document is updated. Unlike the
document_state_changed event which tracks all status transitions,
this event specifically indicates that the document has been modified
and reverted to a draft state, allowing for further edits or updates.

This event is useful for:

• Syncing document updates with external systems
• Audit logging and compliance tracking for document modifications
• Triggering notifications or workflows when documents are edited
• Maintaining version control and change history
• Implementing approval workflows for document changes

Note: The webhook payload structure is synchronized with the
Document State Changed webhook and partially mirrors the Document
Details API response, providing comprehensive document information
captured at the time of update.

Security Note: All webhook requests include an HMAC-SHA256
signature for verification using your shared key.