refactor: comprehensive frontend review — consistency, a11y, code quality

- Replace event dispatchers with BookingContext (Hero, Header, FloatingContact)
- Add focus trap hook for modals (SignupModal, NewsModal)
- Extract shared components: CollapsibleSection, ConfirmDialog, PriceField, AdminSkeleton
- Add delete confirmation dialog to ArrayEditor
- Replace hardcoded colors (#050505, #0a0a0a, #c9a96e, #2ecc71) with theme tokens
- Add CSS variables --color-surface-deep/dark for consistent dark surfaces
- Improve contrast: muted text neutral-500 → neutral-400 in dark mode
- Fix modal z-index hierarchy (modals z-60, header z-50, floats z-40)
- Consolidate duplicate formatDate → shared formatting.ts
- Add useMemo to TeamProfile groupMap computation
- Fix typography: responsive price text in Pricing section
- Add ARIA labels/expanded to FAQ, OpenDay, ArrayEditor grip handles
- Hide number input spinners globally
- Reorder admin sidebar: Dashboard → SEO → Bookings → site section order
- Use shared PriceField in Open Day editor
- Fix schedule grid first time slot (09:00) clipped by container
- Fix pre-existing type errors (bookings, hero, db interfaces)

src/app/admin/_components/PriceField.tsx

@@ -0,0 +1,33 @@
+"use client";
+
+interface PriceFieldProps {
+  label: string;
+  value: string;
+  onChange: (v: string) => void;
+  placeholder?: string;
+}
+
+export function PriceField({ label, value, onChange, placeholder = "0" }: PriceFieldProps) {
+  const raw = value.replace(/\s*BYN\s*$/i, "").trim();
+
+  return (
+    <div>
+      <label className="block text-sm text-neutral-400 mb-1.5">{label}</label>
+      <div className="flex rounded-lg border border-white/10 bg-neutral-800 focus-within:border-gold transition-colors">
+        <input
+          type="text"
+          value={raw}
+          onChange={(e) => {
+            const v = e.target.value;
+            onChange(v ? `${v} BYN` : "");
+          }}
+          placeholder={placeholder}
+          className="flex-1 bg-transparent px-4 py-2.5 text-white placeholder-neutral-500 outline-none min-w-0"
+        />
+        <span className="flex items-center pr-4 text-sm font-medium text-gold select-none">
+          BYN
+        </span>
+      </div>
+    </div>
+  );
+}