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/_components/PriceField.tsx

@@ -12,8 +12,8 @@ export function PriceField({ label, value, onChange, placeholder = "0" }: PriceF
 
   return (
     <div>
-      <label className="block text-sm text-neutral-400 mb-1.5">{label}</label>
-      <div className="flex rounded-lg border border-white/10 bg-neutral-800 focus-within:border-gold transition-colors">
+      <label className="block text-sm text-neutral-500 mb-1.5 dark:text-neutral-400">{label}</label>
+      <div className="flex rounded-lg border border-neutral-200 bg-neutral-100 focus-within:border-gold transition-colors dark:border-white/10 dark:bg-neutral-800">
         <input
           type="text"
           inputMode="decimal"
@@ -23,7 +23,7 @@ export function PriceField({ label, value, onChange, placeholder = "0" }: PriceF
             onChange(v ? `${v} BYN` : "");
           }}
           placeholder={placeholder}
-          className="flex-1 bg-transparent px-4 py-2.5 text-white placeholder-neutral-500 outline-none min-w-0"
+          className="flex-1 bg-transparent px-4 py-2.5 text-neutral-900 placeholder-neutral-400 outline-none min-w-0 dark:text-white dark:placeholder-neutral-500"
         />
         <span className="flex items-center pr-4 text-sm font-medium text-gold select-none">
           BYN