Stage 6 (part 2): rest of the client app in the new style, promo code in the order form

Profile with club card, plum theme for buttons/selections and the sticky total,
move screens with the full-width hero, services/docs headers, empty docs fix.
Promo code field: applies to the quote, shows why a code is rejected,
says when the membership discount is bigger.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

apps/miniapp-client/src/screens/Services.tsx

@@ -2,7 +2,7 @@ import { useQuery } from '@tanstack/react-query';
 import { CATEGORY_ICON, Center, Icon, Spinner, type CategoryCode } from '@barev/ui';
 import { useI18n, useLocation, useTRPC } from '@barev/web';
 import { useEffect } from 'react';
-import { levelDiscount, PageHead, toneClass, type Level } from '../lib.tsx';
+import { levelDiscount, toneClass, type Level } from '../lib.tsx';
 
 /** Каталог: направления со скидкой по уровню клиента; услуги без онлайн-записи — заявка «перезвоните» */
 export function Services() {
@@ -25,7 +25,9 @@ export function Services() {
   const level = catalog.data.level as Level;
   return (
     <main className="app">
-      <PageHead title={t('client.services.title')} back={false} />
+      <header className="screen-head">
+        <h1 className="screen-head__title">{t('client.services.title')}</h1>
+      </header>
       {catalog.data.categories
         .filter((c) => c.code !== 'PERKS')
         .map((c) => (