fix: Update subtitle download function to return duration_mins

summarize_yt/cli.py

@@ -88,7 +88,7 @@ def download_subtitles(url: str, quiet: bool = False) -> Tuple[bool, Optional[Pa
             
         if not vtt_files:
             print("No VTT file found after download", file=sys.stderr)
-            return False, None
+            return False, None, 0
 
         return True, vtt_files[0], duration_mins
 
@@ -98,7 +98,7 @@ def download_subtitles(url: str, quiet: bool = False) -> Tuple[bool, Optional[Pa
             print(f"Debug: Full exception info: {type(e).__name__}: {str(e)}")
             import traceback
             traceback.print_exc()
-        return False, None
+        return False, None, 0
 
 
 def clean_vtt_text(text: str) -> str: