Home keeps its navigation when openvibe.network is down (WS-P task 5): a plain nav (home, Scraplandia, the network sites) shows until the shared navbar mounts, and the theme loader is deferred so a slow openvibe.network never holds the first paint (the inline colours cover it)

ddiff --git a/apps/client/index.html b/apps/client/index.html
iindex 431948f..c84cb1d 100644
---- a/apps/client/index.html
++++ b/apps/client/index.html
@@@ -9,7 +9,8 @@
        content="The games arm of the OpenVibe network. Play Scraplandia — scrappy multiplayer survival-building in Scrap City — in your browser, no download."
      />
      <!-- The OpenVibe Frame: the user's theme before first paint, then navbar + footer. -->
--    <script src="https://openvibe.network/shared/theme-loader.js"></script>
++    <!-- Deferred: a slow or unreachable openvibe.network never holds the first paint (the inline colours above cover it). -->
++    <script src="https://openvibe.network/shared/theme-loader.js" defer></script>
      <script src="https://openvibe.network/shared/navbar.js" defer></script>
      <script src="https://openvibe.network/shared/footer.js" defer></script>
      <link rel="canonical" href="https://openvibe.games/" />
@@@ -386,6 +387,24 @@
          max-width: 1200px;
          margin: 0 auto;
        }
++      /* Navigation that works without openvibe.network (roadmap WS-P task 5): shown until the shared
++         navbar mounts, which fills #navbar-mount and hides this. */
++      .ov-nav-fallback {
++        position: relative;
++        z-index: 5;
++        display: flex;
++        flex-wrap: wrap;
++        align-items: center;
++        gap: 6px 16px;
++        padding: 12px 20px;
++        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
++        font: 500 14px/1.4 system-ui, sans-serif;
++      }
++      .ov-nav-fallback a { color: inherit; text-decoration: none; opacity: 0.85; }
++      .ov-nav-fallback a:hover, .ov-nav-fallback a:focus-visible { opacity: 1; text-decoration: underline; }
++      .ov-nav-fallback .home { font-weight: 700; opacity: 1; }
++      .ov-nav-fallback .spacer { flex: 1; }
++      #navbar-mount:not(:empty) + .ov-nav-fallback { display: none; }
      </style>
    </head>
    <body>
@@@ -393,6 +412,16 @@
      <canvas class="stars" id="stars"></canvas>
  
      <div id="navbar-mount"></div>
++    <nav class="ov-nav-fallback" aria-label="Site">
++      <a class="home" href="/">OpenVibe.Games</a>
++      <a href="https://play.openvibe.games">Play Scraplandia</a>
++      <span class="spacer"></span>
++      <a href="https://openvibe.live/">Live</a>
++      <a href="https://openvibe.tools/">Tools</a>
++      <a href="https://openvibe.community/">Community</a>
++      <a href="https://openvibe.media/">Media</a>
++      <a href="https://openvibe.network/">Network</a>
++    </nav>
  
      <header>
        <h1 class="hero-title">Open<b>Vibe.Games</b></h1>