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

assets/templates/asset_audit_list.html

@@ -5,59 +5,53 @@
 
 {% block js %}
     <script>
-    $('document').ready(function(){
-        $('#asset-search-form').submit(function () {
-         $('#searchButton').focus().click();
-         return false;
+    ready(function(){
+        document.getElementById('asset-search-form').addEventListener('submit', function (e) {
+            e.preventDefault();
+            document.getElementById('searchButton').focus();
+            document.getElementById('searchButton').click();
         });
-        $('#searchButton').click(function (e) {
+        document.getElementById('searchButton').addEventListener('click', function (e) {
              e.preventDefault();
-             var url = "{% url 'asset_audit' None %}".replace('None', $("#{{form.q.id_for_label}}").val());
-             $.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();
-                        });
+             var url = "{% url 'asset_audit' None %}".replace('None', document.getElementById("{{form.q.id_for_label}}").value);
+             fetch(url, {method: 'HEAD', credentials: 'same-origin'})
+                .then(function (response) {
+                    if (!response.ok) {
+                        throw new Error(response.statusText);
                     }
-                },
-                error:function(){
-                    $("#error404").attr("hidden", false);
-                }
-             });
+                    modaltarget = undefined;
+                    modalobject = "";
+                    return loadModal(url);
+                })
+                .catch(function () {
+                    document.getElementById("error404").hidden = false;
+                });
         });
     });
     function onAuditClick(assetID) {
-         $('#' + assetID).remove();
+         document.getElementById(assetID).remove();
     }
-    $('#modal').on('hidden.bs.modal', function (e) {
-      searchbar = document.getElementById('id_q');
+    document.getElementById('modal').addEventListener('hidden.bs.modal', function () {
+      var searchbar = document.getElementById('id_q');
       searchbar.value = "";
-      setTimeout(searchbar.focus(), 2000);
-    })
+      searchbar.focus();
+    });
     </script>
 {% endblock %}
 
 {% block content %}
 <div id="error404" class="alert alert-danger alert-dismissable" hidden=true>
-	<button type="button" class="close" data-dismiss="alert" aria-hidden="true">&times;</button>
+	<button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
 	<span>Asset with that ID does not exist!</span>
 </div>
 
 <form id="asset-search-form" class="mb-3" method="GET">
-  <div class="form-group form-row">
+  <div class="mb-3 row g-2">
       <h3>Audit Asset:</h3>
       <div class="input-group input-group-lg">
         {% render_field form.q|add_class:'form-control' placeholder='Enter Asset ID' autofocus="true" %}
-        <div class="input-group-append">
-            <label for="q" class="sr-only">Asset ID:</label>
+        <label for="q" class="visually-hidden">Asset ID:</label>
             <a id="searchButton" class="btn btn-primary" class="submit" type="submit">Search</a>
-        </div>
       </div>
   </div>
 </form>