unify folder naming with resolved audio profiles across providers

internal/provider/provider.go

@@ -8,6 +8,16 @@ type Downloadable struct {
 	Source    string
 	Cipher    string
 	TrackID   string
+	Audio     AudioProfile
+}
+
+type AudioProfile struct {
+	Container    string
+	Codec        string
+	Quality      string
+	BitDepth     int
+	SamplingRate string
+	BitrateKbps  int
 }
 
 type Client interface {