feat: tag all PocketBase fetches for ISR cache invalidation

Each getCollection/getFirstRecord call now passes the collection name
as a cache tag so revalidateTag can target individual collections.

src/widgets/BioSection/ui/BioSection/BioSection.tsx

@@ -8,7 +8,7 @@ import { RichText } from '$shared/ui';
  * Displays personal biography content from PocketBase.
  */
 export default async function BioSection() {
-  const data = await getFirstRecord<PageContentRecord>('bio');
+  const data = await getFirstRecord<PageContentRecord>('bio', { tags: ['bio'] });
 
   if (!data) {
     notFound();