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.sum

@@ -6,6 +6,8 @@ gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018072517-d0173f795d2a h1:y
 gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018072517-d0173f795d2a/go.mod h1:L+GcqPRZiu0Srq6+YxfdLztltXV8DcxKjNUOXWJvR9o=
 gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018080126-dbb823ade349 h1:3Rru+kVwHrDZwO1AcJ6e/ia/O4XKt6A3Nux1WXmDBDE=
 gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018080126-dbb823ade349/go.mod h1:L+GcqPRZiu0Srq6+YxfdLztltXV8DcxKjNUOXWJvR9o=
+gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018120746-dbf9a46bb2e7 h1:efp/oD3K2Pwm+fRuGKrQo/VMYKfj0VVenn1zvZEBB/0=
+gitea.mrixs.me/Mrixs/yandex-music-api-go v0.0.0-20261018120746-dbf9a46bb2e7/go.mod h1:L+GcqPRZiu0Srq6+YxfdLztltXV8DcxKjNUOXWJvR9o=
 github.com/bogem/id3v2 v1.2.0 h1:hKDF+F1gOgQ5r1QmBCEZUk4MveJbKxCeIDSBU7CQ4oI=
 github.com/bogem/id3v2 v1.2.0/go.mod h1:t78PK5AQ56Q47kizpYiV6gtjj3jfxlz87oFpty8DYs8=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=