feat: complete dashboard redesign, proxy unification, and Windows compatibility fixes

dashboard/src/index.css

@@ -71,6 +71,10 @@ html, body, #root {
 ::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }
 
 /* ─── Animations ───────────────────────────────────────────────────────────── */
+@keyframes spin {
+  to { transform: rotate(360deg); }
+}
+
 @keyframes slideInUp {
   from { opacity: 0; transform: translateY(10px); }
   to { opacity: 1; transform: translateY(0); }