ios: hide progress controls for live streams

ios/QueueCube/Views/NowPlayingMiniView.swift

@@ -61,7 +61,7 @@ struct NowPlayingMiniView: View {
             }
             .padding(EdgeInsets(top: 4.0, leading: 14.0, bottom: 4.0, trailing: 10.0))
 
-            if model.playbackDuration != nil {
+            if model.seekablePlaybackDuration != nil {
                 TimelineView(.periodic(from: .now, by: 1.0)) { context in
                     ProgressView(value: model.playbackProgress(at: context.date) ?? 0.0)
                         .progressViewStyle(.linear)

ios/QueueCube/Views/NowPlayingView.swift

@@ -40,6 +40,11 @@ class NowPlayingViewModel
         return duration
     }
 
+    var seekablePlaybackDuration: Double? {
+        guard isSeekable else { return nil }
+        return playbackDuration
+    }
+
     var displayedPlaybackPosition: Double {
         displayedPlaybackPosition(at: .now)
     }
@@ -55,8 +60,8 @@ class NowPlayingViewModel
     }
 
     func playbackProgress(at date: Date) -> Double? {
-        guard let playbackDuration else { return nil }
+        guard let seekablePlaybackDuration else { return nil }
-        return displayedPlaybackPosition(at: date) / playbackDuration
+        return displayedPlaybackPosition(at: date) / seekablePlaybackDuration
     }
 
     func syncPlaybackPosition(_ position: Double?, duration: Double?, isPlaying: Bool, isSeekable: Bool) {
@@ -108,7 +113,7 @@ struct NowPlayingView: View
                 
                 Spacer(minLength: 20.0)
 
-                if let duration = model.playbackDuration {
+                if let duration = model.seekablePlaybackDuration {
                     TimelineView(.periodic(from: .now, by: 1.0)) { context in
                         VStack(spacing: 2.0) {
                             Slider(
@@ -116,7 +121,7 @@ struct NowPlayingView: View
                                 in: 0.0...duration,
                                 onEditingChanged: playbackPositionEditingChanged
                             )
-                            .disabled(!model.isSeekable || nothingQueued)
+                            .disabled(nothingQueued)
 
                             HStack {
                                 Text(formatTime(model.displayedPlaybackPosition(at: context.date)))