feat: add revision support to template API endpoints

Add optional 'revision' parameter to PUT /api/templates/:id and
PUT /api/templates/:id/documents. When present, creates a template
version snapshot (same mechanism as the UI editor's Save button).

This enables API consumers (e.g., deploy-docuseal.py) to create
revision history entries when updating templates programmatically.

Usage: include "revision": true in the request body.
Omit the parameter to skip version creation (backwards compatible).

app/controllers/api/templates_controller.rb

@@ -71,6 +71,8 @@ module Api
       WebhookUrls.enqueue_events(@template, 'template.updated')
       WebhookUrls.enqueue_events(@template, 'template.archived') if archived == true
 
+      TemplateVersions.find_or_create_for(@template, author: current_user) if params[:revision].present?
+
       render json: @template.as_json(only: %i[id updated_at])
     end
 

app/controllers/api/templates_documents_controller.rb

@@ -22,6 +22,8 @@ module Api
       SearchEntries.enqueue_reindex(@template)
       WebhookUrls.enqueue_events(@template, 'template.updated')
 
+      TemplateVersions.find_or_create_for(@template, author: current_user) if params[:revision].present?
+
       render json: Templates::SerializeForApi.call(@template)
     end