Unify layouts and create CatalogPage component

- MainNavigation: center tabs on page (absolute positioning)
- SubNavigation: align left instead of center
- Create CatalogPage universal component for list+map pages
- Migrate catalog pages (offers, suppliers, hubs) to CatalogPage
- Remove PageHeader from clientarea pages (redundant with navigation)
- Add topnav layout to supplier detail page

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/pages/clientarea/addresses/index.vue

@@ -1,11 +1,6 @@
 <template>
   <Section variant="plain" paddingY="md">
     <Stack gap="6">
-      <PageHeader
-        :title="t('profileAddresses.header.title')"
-        :actions="[{ label: t('profileAddresses.actions.add'), icon: 'lucide:plus', to: localePath('/clientarea/addresses/new') }]"
-      />
-
       <Card v-if="isLoading" padding="lg">
         <Stack align="center" gap="3">
           <Spinner />

app/pages/clientarea/orders/index.vue

@@ -1,11 +1,6 @@
 <template>
   <Section variant="plain" paddingY="md">
     <Stack gap="6">
-      <PageHeader
-        :title="$t('dashboard.orders')"
-        :actions="[{ label: t('ordersList.actions.new_calc'), icon: 'lucide:plus', to: localePath('/clientarea') }]"
-      />
-
       <Alert v-if="hasError" variant="error">
         <Stack gap="2">
           <Heading :level="4" weight="semibold">{{ $t('common.error') }}</Heading>