Add internal title for exercise

The internal title is designed to provide an alternative title for teachers. It is not exposed to learners.

app/controllers/exercises_controller.rb

@@ -208,6 +208,7 @@ class ExercisesController < ApplicationController
                              :allow_file_creation,
                              :allow_auto_completion,
                              :title,
+                             :internal_title,
                              :expected_difficulty,
                              :tips,
                              files_attributes: file_attributes,

app/models/exercise.rb

@@ -614,7 +614,7 @@ class Exercise < ApplicationRecord
   end
 
   def self.ransackable_attributes(_auth_object = nil)
-    %w[title]
+    %w[title internal_title]
   end
 
   def self.ransackable_associations(_auth_object = nil)

app/views/exercises/_form.html.slim

@@ -12,6 +12,10 @@
   .mb-3
     = f.label(:title, class: 'form-label')
     = f.text_field(:title, class: 'form-control', required: true)
+  .mb-3
+    = f.label(:internal_title, class: 'form-label')
+    = f.text_field(:internal_title, class: 'form-control')
+    .help-block.form-text == t('.hints.internal_title')
   .mb-3
     = f.label(:description, class: 'form-label')
     = f.pagedown :description, input_html: { preview: true, rows: 10 }

app/views/exercises/index.html.slim

@@ -5,8 +5,8 @@ h1 = Exercise.model_name.human(count: 2)
     = f.label(:execution_environment_id_eq, t('activerecord.attributes.exercise.execution_environment'), class: 'visually-hidden form-label')
     = f.collection_select(:execution_environment_id_eq, @execution_environments.with_exercises, :id, :name, class: 'form-control', prompt: t('activerecord.attributes.exercise.execution_environment'))
   .col-auto
-    = f.label(:title_cont, t('activerecord.attributes.exercise.title'), class: 'visually-hidden form-label')
-    = f.search_field(:title_cont, class: 'form-control', placeholder: t('activerecord.attributes.exercise.title'))
+    = f.label(:title_or_internal_title_cont, t('activerecord.attributes.exercise.title'), class: 'visually-hidden form-label')
+    = f.search_field(:title_or_internal_title_cont, class: 'form-control', placeholder: t('activerecord.attributes.exercise.title'))
 
 .table-responsive
   table.table.mt-2
@@ -27,7 +27,12 @@ h1 = Exercise.model_name.human(count: 2)
     tbody
       - @exercises.each do |exercise|
         tr data-id=exercise.id
-          td.p-1.pt-2 = link_to_if(policy(exercise).show?, exercise.title, exercise, 'data-turbolinks' => "false")
+          td.p-1.pt-2
+            = link_to_if(policy(exercise).show?, exercise.title, exercise, 'data-turbolinks' => "false")
+            - if exercise.internal_title.present?
+              p.mb-0.text-muted
+                i.fa-solid.fa-arrow-turn-up.fa-rotate-90
+                span = exercise.internal_title
           td.p-1.pt-2 = link_to_if(exercise.execution_environment && policy(exercise.execution_environment).show?, exercise.execution_environment, exercise.execution_environment)
           td.p-1.pt-2 = exercise.files.filter(&:teacher_defined_assessment?).length
           td.p-1.pt-2 = exercise.maximum_score

app/views/exercises/show.html.slim

@@ -5,7 +5,12 @@
   - append_javascript_pack_tag('highlight')
   - append_stylesheet_pack_tag('highlight')
 
-h1.d-inline-block = @exercise
+h1.d-inline-block
+  = @exercise
+  - if @exercise.internal_title.present?
+    p.mb-0.ps-1.text-muted.small
+      i.fa-solid.fa-arrow-turn-up.fa-rotate-90
+      span = @exercise.internal_title
 .btn-group.float-end
   = render('shared/edit_button', object: @exercise)
   button.btn.btn-secondary.float-end.dropdown-toggle data-bs-toggle='dropdown' type='button'
@@ -19,6 +24,7 @@ h1.d-inline-block = @exercise
     li = link_to(t('exercises.export_codeharbor.label'), '', class: 'dropdown-item export-start', data: {'exercise-id' => @exercise.id}) if policy(@exercise).export_external_confirm?
 
 = row(label: 'exercise.title', value: @exercise.title)
+= row(label: 'exercise.internal_title', value: @exercise.internal_title)
 = row(label: 'exercise.user', value: link_to_if(policy(@exercise.author).show?, @exercise.author, @exercise.author))
 = row(label: 'exercise.description', value: render_markdown(@exercise.description), class: 'm-0')
 = row(label: 'exercise.execution_environment', value: link_to_if(@exercise.execution_environment && policy(@exercise.execution_environment).show?, @exercise.execution_environment, @exercise.execution_environment))
@@ -57,4 +63,4 @@ ul.list-unstyled#files
             .clearfix = link_to(t('shared.destroy'), file, class:'btn btn-warning btn-sm float-end', data: {confirm: t('shared.confirm_destroy')}, method: :delete)
           = render('shared/file', file: file)
 
-= render('shared/modal', id: 'export-modal', title: t('exercises.export_codeharbor.dialogtitle'), template: 'exercises/_export_dialogcontent')
+= render('shared/modal', id: 'export-modal', title: t('exercises.export_codeharbor.dialogtitle'), template: 'exercises/_export_dialogcontent')