only show interventions if condition is met. right now, only show one intervention per user and exercise

app/controllers/exercises_controller.rb

@@ -155,6 +155,12 @@ class ExercisesController < ApplicationController
 
   def implement
     redirect_to(@exercise, alert: t('exercises.implement.no_files')) unless @exercise.files.visible.exists?
+    @show_interventions =
+      if UserExerciseIntervention.find_by(exercise: @exercise, user: current_user)
+        "false"
+      else
+        "true"
+      end
     @submission = current_user.submissions.where(exercise_id: @exercise.id).order('created_at DESC').first
     @files = (@submission ? @submission.collect_files : @exercise.files).select(&:visible).sort_by(&:name_with_extension)
     @paths = collect_paths(@files)