fix(feeds): RSS improve torrent size parsing (#667)

* Fixes issue 636 - fail to parse torrent size on some RSS feeds when enclosure is a fixed value

* Pick the biggest size

* minor comment

* Updates release size when new parsed string size is bigger

- Sets default size of `Release` to zero (unparsed)
- When there are parsing errors, then it doesn't RESET the size to 0 (assuming a tracker providing some size that can't be parsed)
- Updates the size to the new size only if the parsed size is bigger than the previous.

* fix(feeds): ignore default 39399 enclosure size

---------

Co-authored-by: ze0s <43699394+zze0s@users.noreply.github.com>

internal/feed/rss.go

@@ -113,7 +113,7 @@ func (j *RSSJob) processItem(item *gofeed.Item) *domain.Release {
 		if e.Type == "application/x-bittorrent" && e.URL != "" {
 			rls.TorrentURL = e.URL
 		}
-		if e.Length != "" {
+		if e.Length != "" && e.Length != "39399" {
 			rls.ParseSizeBytesString(e.Length)
 		}
 	}
@@ -154,11 +154,9 @@ func (j *RSSJob) processItem(item *gofeed.Item) *domain.Release {
 		rls.Uploader += v.Name
 	}
 
-	if rls.Size == 0 {
-		// parse size bytes string
-		if sz, ok := item.Custom["size"]; ok {
-			rls.ParseSizeBytesString(sz)
-		}
+	// When custom->size and enclosures->size differ, `ParseSizeBytesString` will pick the largest one.
+	if size, ok := item.Custom["size"]; ok {
+		rls.ParseSizeBytesString(size)
 	}
 
 	// additional size parsing