feat: Support for Whatsapp Cloud API (#4938)

Ability to configure Whatsapp Cloud API Inboxes

fixes: #4712

app/controllers/concerns/meta_token_verify_concern.rb

@@ -0,0 +1,20 @@
+# services from Meta (Prev: Facebook) needs a token verification step for webhook subscriptions,
+# This concern handles the token verification step.
+
+module MetaTokenVerifyConcern
+  def verify
+    service = is_a?(Webhooks::WhatsappController) ? 'whatsapp' : 'instagram'
+    if valid_token?(params['hub.verify_token'])
+      Rails.logger.info("#{service.capitalize} webhook verified")
+      render json: params['hub.challenge']
+    else
+      render status: :unauthorized, json: { error: 'Error; wrong verify token' }
+    end
+  end
+
+  private
+
+  def valid_token?(_token)
+    raise 'Overwrite this method your controller'
+  end
+end