Add news API functionality and update tests for article retrieval

src/app/news/news_api.py

@@ -17,16 +17,17 @@ class NewsAPI:
         assert api_key is not None, "NEWS_API_KEY environment variable not set"
 
         self.client = newsapi.NewsApiClient(api_key=api_key)
-        self.category = "business"
-        self.language = "en"
-        self.page_size = 100
+        self.category = "business" # Cryptocurrency is under business
+        self.language = "en" # TODO Only English articles for now?
+        self.max_page_size = 100
 
     def get_top_headlines(self, query:str, total:int=100) -> list[Article]:
-        page_size = min(self.page_size, total)
+        page_size = min(self.max_page_size, total)
         pages = (total // page_size) + (1 if total % page_size > 0 else 0)
+
         articles = []
         for page in range(1, pages + 1):
-            headlines = self.client.get_top_headlines(category=self.category, language=self.language, page_size=page_size, page=page)
+            headlines = self.client.get_top_headlines(q=query, category=self.category, language=self.language, page_size=page_size, page=page)
             results = [result_to_article(article) for article in headlines.get("articles", [])]
             articles.extend(results)
         return articles