feat: refresh dashboard design with fantasy RPG aesthetic

- Replace Inter font with Cinzel (headings) + Jura (body)
- Deepen dark background palette with atmospheric gradient orbs
- Add subtle noise texture overlay for depth
- Refine glass cards with animated gradient border glow on hover
- Sharpen accent colors: violet #8b5cf6 + cyan #22d3ee
- Improve button tactile feedback and shadow system
- Add k8s manifests for minikube local deployment

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/GmRelay.Web/Components/Layout/NavMenu.razor.css

@@ -23,12 +23,11 @@
 }
 
 .nav-brand-text {
+    font-family: 'Cinzel Decorative', 'Cinzel', serif;
     font-size: 1.125rem;
     font-weight: 700;
-    background: var(--accent-gradient);
-    -webkit-background-clip: text;
-    -webkit-text-fill-color: transparent;
-    background-clip: text;
+    letter-spacing: 0.04em;
+    color: var(--text-primary);
 }
 
 .nav-toggle {
@@ -87,9 +86,10 @@
 }
 
 .nav-section ::deep .nav-item.active {
-    background: rgba(124, 58, 237, 0.15);
-    color: var(--accent-primary);
-    border: 1px solid rgba(124, 58, 237, 0.2);
+    background: linear-gradient(135deg, rgba(139, 92, 246, 0.15) 0%, rgba(34, 211, 238, 0.08) 100%);
+    color: var(--text-accent);
+    border: 1px solid rgba(139, 92, 246, 0.25);
+    box-shadow: 0 0 12px rgba(139, 92, 246, 0.1);
 }
 
 .nav-icon {
@@ -145,7 +145,7 @@
     border: 1px solid transparent;
     border-radius: var(--radius-sm);
     color: var(--text-muted);
-    font-family: 'Inter', sans-serif;
+    font-family: 'Jura', sans-serif;
     font-size: 0.8125rem;
     cursor: pointer;
     transition: all var(--transition-normal);