Fix mobile responsiveness across all pages

- PosPage: rooms list becomes horizontal scroll row on mobile instead of w-56 sidebar
- AvailabilityPage: edit panel stacks below grid on mobile (was fixed w-80 side panel)
- UsersPage roles tab: sidebar stacks above permissions on mobile
- All page containers: p-6 → p-4 md:p-6 (TariffsPage, DiscountsPage, MaintenancePage, ReportsPage, DynamicPricingPage, GuestsPage, LoyaltyPage)
- Stats grids: lg:grid-cols-4 → md:grid-cols-4 (GuestsPage, TariffsPage, DiscountsPage, MaintenancePage, ReportsPage, LoyaltyPage)
- Modal form grids: grid-cols-3 → grid-cols-1 sm:grid-cols-3, grid-cols-5 → grid-cols-3 sm:grid-cols-5, grid-cols-4 → grid-cols-2 sm:grid-cols-4
- PosPage modals: fixed w-80/w-96 → responsive w-[calc(100vw-2rem)] sm:w-80/96

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/pages/LoyaltyPage.tsx

@@ -815,7 +815,7 @@ export function LoyaltyPage() {
   const totalPoints   = MOCK_GUESTS.reduce((s, g) => s + g.points, 0)
 
   return (
-    <div className="p-6 space-y-5">
+    <div className="p-4 md:p-6 space-y-5">
       {/* Header */}
       <div className="flex items-center justify-between">
         <div>
@@ -837,7 +837,7 @@ export function LoyaltyPage() {
       </div>
 
       {/* Stats */}
-      <div className="grid grid-cols-2 lg:grid-cols-4 gap-3">
+      <div className="grid grid-cols-2 md:grid-cols-4 gap-3">
         {[
           { label: 'Участников программы',   value: activeGuests,                         icon: User,       color: 'text-brand-600 dark:text-brand-400',   bg: 'bg-brand-50 dark:bg-brand-900/20' },
           { label: 'Всего баллов в обороте', value: totalPoints.toLocaleString('ru-RU'),  icon: TrendingUp, color: 'text-amber-600 dark:text-amber-400',   bg: 'bg-amber-50 dark:bg-amber-900/20' },
@@ -885,7 +885,7 @@ export function LoyaltyPage() {
                   {editSettings ? <><Save size={13} /> Сохранить</> : <><Edit2 size={13} /> Изменить</>}
                 </button>
               </div>
-              <div className="grid grid-cols-3 gap-4">
+              <div className="grid grid-cols-1 sm:grid-cols-3 gap-4">
                 {[
                   { label: 'Начисление',   desc: `${settings.pointsPerRuble} балл за 1 ₽`, field: 'pointsPerRuble' as const, unit: 'балл/₽' },
                   { label: 'Ценность',     desc: `1 балл = ${settings.pointValue} ₽`,      field: 'pointValue'     as const, unit: '₽' },