Fix UI issues: 3 columns, SubNav label, back button, sticky map, hover flyTo

- Homepage roles section now shows 3 columns on medium screens
- SubNavigation catalog offers label changed to "Предложения"
- Removed back button from catalog/offers page
- ListMapLayout: sticky map with full height
- ListMapLayout: hover on card flies to location on map

app/pages/index.vue

@@ -5,7 +5,7 @@
           <Heading :level="2">{{ $t('roles.title') }}</Heading>
           <Text align="center" tone="muted">{{ $t('about.description') }}</Text>
 
-          <Grid :cols="1" :lg="3" :gap="6">
+          <Grid :cols="1" :md="3" :gap="6">
             <Card padding="lg">
               <Stack gap="4" align="center">
                 <IconCircle tone="primary">🏭</IconCircle>