Fix get_title and get_provider null safety, add provider edge case tests

src/core/providers/aniworld_provider.py

@@ -373,9 +373,12 @@ class AniworldLoader(Loader):
         title_div = soup.find('div', class_='series-title')
 
         if title_div:
-            title = title_div.find('h1').find('span').text
-            logging.debug(f"Found title: {title}")
-            return title
+            h1_tag = title_div.find('h1')
+            span_tag = h1_tag.find('span') if h1_tag else None
+            if span_tag:
+                title = span_tag.text
+                logging.debug(f"Found title: {title}")
+                return title
 
         logging.warning(f"No title found for key: {key}")
         return ""
@@ -531,7 +534,7 @@ class AniworldLoader(Loader):
 
             redirect_link_tag = link.find('a', class_='watchEpisode')
             redirect_link = (
-                redirect_link_tag['href']
+                redirect_link_tag.get('href')
                 if redirect_link_tag else None
             )