bootstrap: swap BS4 (alexwine) CSS for bootstrap@5 npm

Completes the Bootstrap 4->5 migration now that every jQuery/BS4 widget is React
(navbar, carousel, dropdowns) — plus the feedback toggle here (Feedback.js:
global `$('#feedback-form').toggle()` -> React state).

- Load Bootstrap 5 CSS from the `bootstrap` npm package in client/index.js
  (imported first so app + component styles and react-bootstrap override it).
- Remove the `alexwine:bootstrap-4` meteor package (BS4 CSS + jQuery + BS4 JS).
  jQuery for jquery-validation still comes from the npm `jquery` dep.
- Utility renames to BS5: ml-auto->ms-auto, float-right->float-end,
  btn-block->w-100, data-toggle->data-bs-toggle (FromNow tooltip).
- forms.scss `.form-label` is no longer a shim (BS5 ships it); comment updated.

Full-app build boots clean; server suite 36 passing. Needs a visual staging pass
across all pages (BS4->5 shifts grid gutters/typography); forms should improve
since react-bootstrap v2 already emitted BS5 markup.

imports/ui/components/Feedback/Feedback.js

@@ -18,6 +18,7 @@ import './Feedback.scss';
 class Feedback extends Component {
   constructor(props) {
     super(props);
+    this.state = { open: false };
     this.handleSubmit = this.handleSubmit.bind(this);
     this.onTabClick = this.onTabClick.bind(this);
   }
@@ -50,7 +51,9 @@ class Feedback extends Component {
   }
 
   onTabClick() {
-    $('#feedback-form').toggle('slide');
+    // Was `$('#feedback-form').toggle('slide')` — global jQuery from the BS4
+    // meteor package. React state instead, so nothing depends on that global.
+    this.setState(s => ({ open: !s.open }));
   }
 
   handleSubmit() {
@@ -76,7 +79,7 @@ class Feedback extends Component {
       <div>
         { !this.props.isHome &&
           <div id="feedback">
-            <div id="feedback-form" ref={formdiv => (this.formdiv = formdiv)} style={{ display: 'none' }} className="card">
+            <div id="feedback-form" ref={formdiv => (this.formdiv = formdiv)} style={{ display: this.state.open ? 'block' : 'none' }} className="card">
               <form
                   ref={form => (this.form = form)}
                   className="form card-body"
@@ -109,7 +112,7 @@ class Feedback extends Component {
                   />
                   <Form.Control.Feedback />
                 </Form.Group>
-                <Button type="submit" variant="success" className="float-right" id={testId('sendFeedbackBtn')} >
+                <Button type="submit" variant="success" className="float-end" id={testId('sendFeedbackBtn')} >
                   {t('Enviar')}
                 </Button>
               </form>