fix: comprehensive UI/UX accessibility and usability improvements

Public site: skip-to-content link, mobile menu focus trap + Escape key,
aria-current on nav, keyboard navigation for carousels/tabs/articles,
ARIA roles (tablist/tab/tabpanel, combobox/listbox, region, dialog),
form labels + aria-describedby, 44px touch targets, semantic HTML
(<time>, <del>), prefers-reduced-motion on Hero scroll hijack,
mobile schedule filters, URL hash sync on scroll for correct refresh.

Admin panel: password toggle aria-label, toast aria-live regions,
SelectField keyboard navigation (Arrow/Enter/Escape), aria-invalid
on validation errors, sidebar hamburger aria-label/expanded,
nav aria-label, ArrayEditor aria-expanded on collapsible items.

src/app/admin/login/page.tsx

@@ -2,11 +2,13 @@
 
 import { useState } from "react";
 import { useRouter } from "next/navigation";
+import { Eye, EyeOff } from "lucide-react";
 
 export default function AdminLoginPage() {
   const [password, setPassword] = useState("");
   const [error, setError] = useState("");
   const [loading, setLoading] = useState(false);
+  const [showPassword, setShowPassword] = useState(false);
   const router = useRouter();
 
   async function handleSubmit(e: React.FormEvent) {
@@ -48,19 +50,31 @@ export default function AdminLoginPage() {
           <label htmlFor="password" className="block text-sm text-neutral-400 mb-2">
             Пароль
           </label>
-          <input
-            id="password"
-            type="password"
-            value={password}
-            onChange={(e) => setPassword(e.target.value)}
-            className="w-full rounded-lg border border-white/10 bg-neutral-800 px-4 py-3 text-white placeholder-neutral-500 outline-none focus:border-gold transition-colors"
-            placeholder="Введите пароль"
-            autoFocus
-          />
+          <div className="relative">
+            <input
+              id="password"
+              type={showPassword ? "text" : "password"}
+              value={password}
+              onChange={(e) => setPassword(e.target.value)}
+              className="w-full rounded-lg border border-white/10 bg-neutral-800 px-4 py-3 pr-11 text-white placeholder-neutral-500 outline-none focus:border-gold transition-colors"
+              placeholder="Введите пароль"
+              autoFocus
+              aria-describedby={error ? "login-error" : undefined}
+            />
+            <button
+              type="button"
+              onClick={() => setShowPassword(!showPassword)}
+              aria-label={showPassword ? "Скрыть пароль" : "Показать пароль"}
+              className="absolute right-3 top-1/2 -translate-y-1/2 text-neutral-500 hover:text-white transition-colors"
+              tabIndex={-1}
+            >
+              {showPassword ? <EyeOff size={18} /> : <Eye size={18} />}
+            </button>
+          </div>
         </div>
 
         {error && (
-          <p className="text-sm text-red-400 text-center">{error}</p>
+          <p id="login-error" role="alert" className="text-sm text-red-400 text-center">{error}</p>
         )}
 
         <button