feat: _is_direct_url — route YouTube/SoundCloud links to direct download

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/test_odesli.py

@@ -66,3 +66,23 @@ def test_odesli_resolve_network_error_returns_none(monkeypatch):
         raise mf.RequestException("down")
     monkeypatch.setattr(mf.requests, "get", boom)
     assert mf.odesli_resolve("https://open.spotify.com/track/abc") is None
+
+
+def test_is_direct_url_youtube():
+    assert mf._is_direct_url("https://music.youtube.com/watch?v=abc")
+    assert mf._is_direct_url("https://www.youtube.com/watch?v=abc")
+    assert mf._is_direct_url("https://youtu.be/abc")
+
+
+def test_is_direct_url_soundcloud():
+    assert mf._is_direct_url("https://soundcloud.com/dj/track")
+
+
+def test_is_direct_url_other_platforms_false():
+    assert not mf._is_direct_url("https://open.spotify.com/track/abc")
+    assert not mf._is_direct_url("https://music.apple.com/us/album/x/1?i=2")
+    assert not mf._is_direct_url("https://tidal.com/browse/track/123")
+
+
+def test_is_direct_url_youtube_playlist_true():
+    assert mf._is_direct_url("https://www.youtube.com/playlist?list=PLabc")