fix: search continuations should return a Search class

Why? To keep things consistent.

lib/parser/youtube/History.js

@@ -29,8 +29,8 @@ class History {
     this.feed_actions = secondary_contents?.contents || null;
     
     this.sections = observe(contents.map((section) => ({
-      title: section.header.title,
-      items: section.contents
+      header: section.header,
+      contents: section.contents
     })));
   }
   

lib/parser/youtube/Library.js

@@ -26,9 +26,9 @@ class Library {
     this.profile = { stats, user_info };
     
     this.sections = observe(shelves.map((shelf) => ({
-      title: shelf.title.toString(),
-      items: shelf.content.items,
       type: shelf.icon_type,
+      title: shelf.title.toString(),
+      contents: shelf.content.items,
       getAll: () => this.#getAll(shelf)
     })));
   }

lib/parser/youtube/Search.js

@@ -41,11 +41,11 @@ class Search extends Feed {
       header: card_list?.header || null,
       /** @type {import('../contents/classes/SearchRefinementCard')} */
       cards: card_list?.cards || []
-    };
+    }
   }
   
   /**
-   * Applies given refinement card and returns a new {@link Feed} object.
+   * Applies given refinement card and returns a new {@link Search} object.
    *
    * @param {import('../contents/classes/SearchRefinementCard') | string} card - refinement card object or query
    * @returns {Promise.<Feed>}
@@ -66,13 +66,23 @@ class Search extends Feed {
     }
     
     const page = await target_card.endpoint.call(this.actions);
-    return new Feed(this.actions, page, true);
+    return new Search(this.actions, page, true);
   }
   
   /** @type {string[]} */
   get refinement_card_queries() {
     return this.refinement_cards.cards.map((card) => card.query);
   }
+  
+  /**
+   * Retrieves next batch of results.
+   * 
+   * @returns {Promise.<Search>}
+   */
+  async getContinuation() {
+    const continuation = await this.getContinuationData();
+    return new Search(this.actions, continuation, true);
+  }
 }
 
 module.exports = Search;