Increase max_length for bart-large-cnn

I'm hoping this will improve the summaries because right now it is
mostly just repeating the titles of the articles which is not useful at
all.

May need to switch back to a GPT-based model if this doesn't work.

src/lib.rs

@@ -126,7 +126,7 @@ async fn request_ai_summarization(
     let client = reqwest::Client::new();
     let request_body = SummarizeRequest {
         input_text: input,
-        max_length: 512,
+        max_length: 1024,
     };
 
     let response = client