Switch Font Awesome CDN from cdnjs to jsdelivr

Icons weren't rendering (glyph placeholder text like "F085" showing instead of the actual icon — the browser's font-fallback behavior when no font can render that codepoint, meaning the FA webfont never loaded). Both CDN URLs resolve fine from here, but Bulma (already jsdelivr) renders correctly for the user while cdnjs-hosted Font Awesome didn't — switching to the same jsdelivr provider removes that difference as a variable.

templates/play.html

@@ -8,7 +8,7 @@
 <link rel="stylesheet" href="{{ google_fonts_link }}">
 <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/4.1.1/animate.min.css">
 <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bulma@1.0.2/css/bulma.min.css">
-<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.4/css/all.min.css">
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/@fortawesome/fontawesome-free@5.15.4/css/all.min.css">
 <style>
   body{ margin:0; background:#000; }
   /* ---------- Zone de jeu à proportion fixe (voir #playFrame) ----------

templates/screen_edit.html

@@ -5,7 +5,7 @@
 {% block extra_head %}
 <link rel="stylesheet" href="{{ google_fonts_link }}">
 <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/4.1.1/animate.min.css">
-<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.4/css/all.min.css">
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/@fortawesome/fontawesome-free@5.15.4/css/all.min.css">
 {% endblock %}
 {% block breadcrumb %}
 <li><a href="{{ url_for('game_dashboard', slug=game.slug) }}">{{ game.name }}</a></li>