fix(guides/routing): update Page interface and add link to API ref

Closes: withastro#8929

src/content/docs/en/guides/routing.mdx

@@ -407,7 +407,7 @@ interface Page<T = any> {
 	total: number;
 	/** the current page number, starting from 1 */
 	currentPage: number;
-	/** number of items per page (default: 25) */
+	/** number of items per page (default: 10) */
 	size: number;
 	/** number of last page */
 	lastPage: number;
@@ -418,10 +418,16 @@ interface Page<T = any> {
 		prev: string | undefined;
 		/** url of the next page (if there is one) */
 		next: string | undefined;
+		/** url of the first page (if the current page is not the first page) */
+		first: string | undefined;
+		/** url of the next page (if the current page in not the last page) */
+		last: string | undefined;
 	};
 }
 ```
 
+<ReadMore>Learn more about [`page` prop](/en/reference/api-reference/#the-pagination-page-prop).</ReadMore>
+
 ### Nested Pagination
 
 A more advanced use-case for pagination is **nested pagination.** This is when pagination is combined with other dynamic route params. You can use nested pagination to group your paginated collection by some property or tag.