Classify EE feature as SaaS or SM

if there are two distinct code paths for SaaS or Self Managed.
Reduce chance of mixing the two concepts for new comers.

ee/app/controllers/admin/subscriptions_controller.rb

 # frozen_string_literal: true
 
+# EE:Self Managed
 class Admin::SubscriptionsController < Admin::ApplicationController
   respond_to :html
 

ee/app/controllers/trial_registrations_controller.rb

 # frozen_string_literal: true
 
+# EE:SaaS
+# TODO: namespace https://gitlab.com/gitlab-org/gitlab/-/issues/338394
 class TrialRegistrationsController < RegistrationsController
   extend ::Gitlab::Utils::Override
 

ee/app/controllers/trials_controller.rb

 # frozen_string_literal: true
 
+# EE:SaaS
+# TODO: namespace https://gitlab.com/gitlab-org/gitlab/-/issues/338394
 class TrialsController < ApplicationController
   include ActionView::Helpers::SanitizeHelper
 

ee/app/helpers/license_helper.rb

@@ -20,6 +20,7 @@ module LicenseHelper
     License.current.present?
   end
 
+  # EE:Self Managed
   def new_trial_url
     return_to_url = CGI.escape(Gitlab.config.gitlab.url)
     uri = URI.parse(::EE::SUBSCRIPTIONS_URL)
@@ -52,6 +53,7 @@ module LicenseHelper
     end
   end
 
+  # EE:Self Managed
   def cloud_license_view_data
     {
       buy_subscription_path: ::EE::SUBSCRIPTIONS_PLANS_URL,

ee/app/views/admin/subscriptions/show.html.haml

+-# EE:Self Managed
 - page_title _('Subscription')
 
 #js-show-subscription-page{ data: cloud_license_view_data }

ee/app/views/dashboard/projects/_blank_state_ee_trial.html.haml

+-# EE:Self Managed
 .blank-state
   .blank-state-icon
     = image_tag("illustrations/lock_promotion.svg", { lazy: false })

ee/app/views/shared/promotions/_promotion_link_project.html.haml

@@ -2,6 +2,7 @@
 - target_blank = local_assigns.fetch :target_blank, false
 
 - if Gitlab::CurrentSettings.should_check_namespace_plan?
+  -# EE:SaaS
   - namespace = @project&.namespace || @group
   - if can?(current_user, :admin_namespace, namespace)
     = link_to s_('Promotions|Try it for free'), new_trial_registration_path(glm_source: 'gitlab.com', glm_content: location), class: 'btn gl-button btn-confirm promotion-trial-cta', target: target_blank ? '_blank' : '_self'
@@ -12,6 +13,7 @@
     - link_start = "<a href='#{user_path(owner)}' rel='noowner noreferrer' target='_blank'>".html_safe
     %p= s_('Promotions|Contact owner %{link_start}%{owner_name}%{link_end} to upgrade the plan.').html_safe % { owner_name: owner.name, link_start: link_start, link_end: '</a>'.html_safe }
 - elsif current_user&.admin?
+  -# EE:Self Managed
   - if License.current&.expired?
     = link_to (!short_form ? s_('Promotions|Buy GitLab Enterprise Edition') : s_('Promotions|Buy EE')), ::EE::SUBSCRIPTIONS_PLANS_URL, class: 'btn gl-button btn-confirm'
   - else