Fix missing H1 on list-style pages via SectionHeading template

SectionHeading always rendered its title as <h2>, so every page whose
only heading came from a shared section component (services hub,
promotions, cases, faq, contact, reviews, blog list) had no <h1> at
all. Add a level prop (default h2) and pass headingLevel="h1" from
each page where that section is the page's own top-level heading.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013otXCiTZsxdZ4SJKZ9wUky

public-site/components/sections/Contact.jsx

@@ -3,7 +3,7 @@ import { MapPin, Phone, Mail, Clock, ArrowRight } from 'lucide-react';
 import Reveal from '../Reveal.jsx';
 import SectionHeading from '../SectionHeading.jsx';
 
-export default function Contact({ contact, compact = false }) {
+export default function Contact({ contact, compact = false, headingLevel = 'h2' }) {
   const rows = contact
     ? [
         { icon: MapPin, label: 'Адрес', value: contact.address },
@@ -39,7 +39,7 @@ export default function Contact({ contact, compact = false }) {
 
   return (
     <section id="contact" className="max-w-6xl mx-auto px-5 sm:px-8 py-20">
-      <SectionHeading eyebrow="contact --reach-us" title="Контакты" />
+      <SectionHeading eyebrow="contact --reach-us" title="Контакты" level={headingLevel} />
       <div className="grid md:grid-cols-2 gap-5">
         <Reveal>
           <div className="rounded-lg border p-5 h-full bg-white border-slate-200 dark:bg-slate-900 dark:border-slate-800">