Migrate to yandex-music-api-go v0.0.0-20261018120746-dbf9a46bb2e7

Library now provides GetTrackDownloadURL (signed URL via XML download_info_url),
so ym-dl delegates to it instead of reimplementing XML parsing and MD5 signing.
Removed local DownloadTrackXML/DownloadInfoXML and unused crypto/md5, encoding/hex,
encoding/xml, io imports from client.go.

Track.Lyrics replaced by LyricsInfo (availability flags only, no text).
Lyrics text requires separate GetTrackLyrics + GetTrackLyricsText calls —
not implemented yet, lyrics field left empty.

go.mod

@@ -3,7 +3,7 @@ module ym-dl
 go 1.27.2
 
 require (
-	gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018080126-dbb823ade349
+	gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018120746-dbf9a46bb2e7
 	github.com/bogem/id3v2 v1.2.0
 	gopkg.in/yaml.v3 v3.0.1
 	modernc.org/sqlite v1.60.1