Bootstrap 5 & remove jQuery (#661)

* build: move frontend assets to Bootstrap 5.3 and Tom Select

* feat: migrate templates and scripts to Bootstrap 5, dropping jQuery

Templates
- Rename Bootstrap 4 classes and data attributes (data-bs-*, ms-/me-/ps-/pe-,
  text-start/end, form-group -> mb-3, input-group wrappers removed, badges,
  custom controls -> form-check/form-select, media -> d-flex, btn-close, ...)
- Dark mode now uses Bootstrap 5.3 colour modes (data-bs-theme on <html>),
  set from <head> to avoid a flash of the light theme
- Remove the Bootstrap 4 /bootstrap/ demo page
- Contextual table classes (table-success etc.) still work as plain
  backgrounds for the rigboard key

JavaScript
- Remove jQuery: src.js/interaction.js and every inline template script are
  rewritten in plain JS on top of small helpers (helpers.js, bundled with
  Bootstrap into jpop.js so inline scripts can use them)
- Replace bootstrap-select/ajax-bootstrap-select with Tom Select. The remote
  search now sends the `q` parameter and reads `text`, which is what the
  API actually uses (the old picker sent `term` and read `label`)
- HTML fragments are fetched with an X-Requested-With header so views keep
  rendering their modal variants, and fetched scripts are re-executed
- Remove the Bootstrap 4 plugin script includes

* fix: stop rigboard header buttons stretching to full width under Bootstrap 5

* fix: restore dark-mode brand colours and contextual table colours under Bootstrap 5

* fix: brighten dark-mode links and make coloured card outlines visible

* fix: calendar layout and grid borders, navbar search button width, guard missing modal links

* fix: readable text in dark-mode Tom Select inputs and placeholders, restore form-control column widths

* build: split the Dockerfile into cached stages with prod and dev targets

* deploy: make compose.yml development-only with live reload, and document it

* fix: keep badge text colour for links inside badges

* fix: restore table-bordered grid lines in dark mode

* fix: include Bootstrap's progress styles and keep progress labels readable

training/templates/trainee_detail.html

@@ -14,35 +14,23 @@
 {% endblock %}
 
 {% block js %}
-<script src="{% static 'js/tooltip.js' %}"></script>
 <script>
-    $('document').ready(function(){
-        $('#add_record').click(function (e) {
-         e.preventDefault();
-         var url = $(this).attr("href");
-         $.ajax({
-            url: url,
-            success: function(){
-                $link = $(this);
-                    // Anti modal inception
-                    if ($link.parents('#modal').length === 0) {
-                        modaltarget = $link.data('target');
-                        modalobject = "";
-                        $('#modal').load(url, function (e) {
-                            $('#modal').modal();
-                            //$(".selectpicker").selectpicker().each(function(){initPicker($(this))});
-                        });
-                    }
-                }
+    ready(function(){
+        var link = document.getElementById('add_record');
+        if (!link) { return; }
+        link.addEventListener('click', function (e) {
+            e.preventDefault();
+            modaltarget = undefined;
+            modalobject = "";
+            loadModal(this.getAttribute("href"));
         });
-     });
     });
 </script>
 {% endblock %}
 
 {% block content %}
 <div class="row">
-    <div class="col-sm-12 text-right">
+    <div class="col-sm-12 text-end">
         <div class="btn-group">
             {% include 'partials/add_qualification.html' %}
             <a href="{% url 'trainee_item_detail' object.pk %}" class="btn btn-info"><span class="fas fa-info-circle"></span> View Detailed Record</a>
@@ -72,16 +60,17 @@
                 {{ level.description|markdown }}
             </div>
             <div class="card-footer">
-                <div class="progress">
-                  <div class="progress-bar progress-bar-striped" role="progressbar" style="width: {{completion}}%" aria-valuenow="{{completion}}" aria-valuemin="0" aria-valuemax="100">{{completion}}% complete</div>
+                <div class="progress" style="height: 1.5rem;">
+                  <div class="progress-bar progress-bar-striped" role="progressbar" style="width: {{completion}}%" aria-valuenow="{{completion}}" aria-valuemin="0" aria-valuemax="100">{% if completion >= 30 %}{{completion}}% complete{% endif %}</div>
                 </div>
+                {% if completion < 30 %}<small class="text-body-secondary">{{completion}}% complete</small>{% endif %}
                 {% if completion == 100 %}
                     <br>
                     {% confirm_button request.user object level as cb %}
                     {% if cb %}
                         <div class="d-flex justify-content-between">{{ cb }}</div>
                     {% else %}
-                        <p class="font-italic pt-2 pb-0">Missing prerequisite level(s)</p>
+                        <p class="fst-italic pt-2 pb-0">Missing prerequisite level(s)</p>
                     {% endif %}
                 {% endif %}
           </div>
@@ -90,7 +79,7 @@
   </div>
 </div>
 <div class="row">
-    <div class="col text-right">
+    <div class="col text-end">
         {% include 'partials/last_edited.html' with target="trainee_history" %}
     </div>
 </div>