Refresh Harbor Gateway branding assets and accent styling

src/web/App.jsx

@@ -35,8 +35,8 @@ function App() {
     const isGateway = state.mode === 'gateway';
     document.title = isGateway ? 'Harbor Gateway' : 'Harbor Connect';
     document.getElementById('harbor-favicon').href = isGateway
-      ? '/harbor-gateway.svg'
-      : '/harbor-connect.svg';
+      ? '/harbor-gateway.svg?v=2'
+      : '/harbor-connect.svg?v=2';
   }, [state?.mode]);
 
   async function run(action) {
@@ -87,7 +87,7 @@ function App() {
   if (!state) return <div className="app-loading">Harbor</div>;
 
   return (
-    <div className="app client-app">
+    <div className={`app client-app${state.mode === 'gateway' ? ' is-gateway-app' : ''}`}>
       <div className="app-body client-mode">
         <main className="app-main">
           <ClientOverviewPage