add webhook event preferences

app/controllers/webhook_preferences_controller.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+class WebhookPreferencesController < ApplicationController
+  EVENTS = %w[
+    form.viewed
+    form.started
+    form.completed
+    submission.archived
+  ].freeze
+
+  before_action :load_account_config
+  authorize_resource :account_config, parent: false
+
+  def create
+    @account_config.value[account_config_params[:event]] = account_config_params[:value] == '1'
+
+    @account_config.save!
+
+    head :ok
+  end
+
+  private
+
+  def load_account_config
+    @account_config =
+      current_account.account_configs.find_or_initialize_by(key: AccountConfig::WEBHOOK_PREFERENCES_KEY)
+    @account_config.value ||= {}
+  end
+
+  def account_config_params
+    params.permit(:event, :value)
+  end
+end