fix(scanner): log warning when metadata extraction fails

Added a warning log when the gotaglib extractor fails to read metadata
from a file. Previously, extraction errors were silently skipped, making
it difficult to diagnose issues with unreadable files during scanning.

Ref: https://github.com/navidrome/navidrome/issues/4604#issuecomment-3865690165
Signed-off-by: Deluan <deluan@navidrome.org>

adapters/gotaglib/gotaglib.go

@@ -49,6 +49,7 @@ func (e extractor) Version() string {
 func (e extractor) extractMetadata(filePath string) (*metadata.Info, error) {
 	f, close, err := e.openFile(filePath)
 	if err != nil {
+		log.Warn("gotaglib: Error reading metadata from file. Skipping", "filePath", filePath, err)
 		return nil, err
 	}
 	defer close()