[Feature Request] Custom Action Buttons (Direct Workflow Triggers)

Description Feature Request: Custom Action Buttons (Direct Workflow Triggers) Description Currently, workflows in Paperless-ngx can only be triggered indirectly by updating a document (e.g., adding a tag, modifying a custom field, etc.). While this workaround functions, it is not user-friendly and introduces potential problems: • It requires modifying document field solely to trigger an action. • It can cause infinite loops if the workflow itself updates the same triggering field (e.g., a tag is added to start a workflow, but not removed afterwards, causing the workflow to repeatedly re-trigger). A more intuitive and safer solution would be to provide dedicated action buttons in the UI that can directly trigger workflows, scripts, or external integrations. Proposed Feature • Add support for custom action buttons in the UI. • Each button could be configured to trigger: - A Paperless-ngx workflow - A server-side script/comman…