Use ClustersFinder in ClustersController#clusters

app/controllers/projects/clusters_controller.rb

 class Projects::ClustersController < Projects::ApplicationController
   before_action :cluster, except: [:login, :index, :new, :new_gcp, :create]
+  before_action :clusters, only: [:index]
   before_action :authorize_read_cluster!
   before_action :authorize_create_cluster!, only: [:new, :new_gcp, :create]
   before_action :authorize_google_api, only: [:new_gcp, :create]
@@ -7,8 +8,6 @@ class Projects::ClustersController < Projects::ApplicationController
   before_action :authorize_admin_cluster!, only: [:destroy]
 
   def index
-    @clusters ||= project.clusters.page(params[:page]).per(20).map { |cluster| cluster.present(current_user: current_user) }
-
     @active_count = project.clusters.enabled.count
     @inactive_count = project.clusters.disabled.count
     @all_count = @active_count + @inactive_count
@@ -101,6 +100,11 @@ class Projects::ClustersController < Projects::ApplicationController
     @cluster ||= project.clusters.find_by(id: params[:id])&.present(current_user: current_user) || render_404
   end
 
+  def clusters
+    scope = params[:scope] || :all
+    @clusters = ClustersFinder.new(project, user, scope).execute
+  end
+
   def create_params
     params.require(:cluster).permit(
       :enabled,