fix: remaining admin & layout light theme polish

- Admin forms, dialogs, and page editors: light-mode borders, text contrast
- YandexMap: theme-aware map styles
- Layout: theme init script adjustments

src/app/admin/login/page.tsx

@@ -36,18 +36,18 @@ export default function AdminLoginPage() {
   }
 
   return (
-    <div className="flex min-h-screen items-center justify-center bg-neutral-950 px-4">
+    <div className="flex min-h-screen items-center justify-center bg-neutral-50 px-4 dark:bg-neutral-950">
       <form
         onSubmit={handleSubmit}
-        className="w-full max-w-sm space-y-6 rounded-2xl border border-white/10 bg-neutral-900 p-8"
+        className="w-full max-w-sm space-y-6 rounded-2xl border border-neutral-200 bg-white p-8 dark:border-white/10 dark:bg-neutral-900"
       >
         <div className="text-center">
-          <h1 className="text-2xl font-bold text-white">BLACK HEART</h1>
-          <p className="mt-1 text-sm text-neutral-400">Панель управления</p>
+          <h1 className="text-2xl font-bold text-neutral-900 dark:text-white">BLACK HEART</h1>
+          <p className="mt-1 text-sm text-neutral-500 dark:text-neutral-400">Панель управления</p>
         </div>
 
         <div>
-          <label htmlFor="password" className="block text-sm text-neutral-400 mb-2">
+          <label htmlFor="password" className="block text-sm text-neutral-500 mb-2 dark:text-neutral-400">
             Пароль
           </label>
           <div className="relative">
@@ -56,7 +56,7 @@ export default function AdminLoginPage() {
               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"
+              className="w-full rounded-lg border border-neutral-200 bg-neutral-100 px-4 py-3 pr-11 text-neutral-900 placeholder-neutral-400 outline-none focus:border-gold transition-colors dark:border-white/10 dark:bg-neutral-800 dark:text-white dark:placeholder-neutral-500"
               placeholder="Введите пароль"
               autoFocus
               aria-describedby={error ? "login-error" : undefined}
@@ -65,7 +65,7 @@ export default function AdminLoginPage() {
               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"
+              className="absolute right-3 top-1/2 -translate-y-1/2 text-neutral-500 hover:text-neutral-900 transition-colors dark:hover:text-white"
               tabIndex={-1}
             >
               {showPassword ? <EyeOff size={18} /> : <Eye size={18} />}