feat: add opening/ending autoskip and correct sponsor hover anchors

Sponsor hover labels used the overlapping chapter midpoint; retain chapter-title lookup but anchor the label to the sponsored range midpoint.

Sources/App/PlayerActions.swift

@@ -206,6 +206,17 @@ struct PlayerMiruroMenu: View {
     }
 }
 
+@MainActor
+struct PlayerOpeningEndingSkipToggle: View {
+    @ObservedObject var model: PlayerModel
+
+    var body: some View {
+        Toggle("Automatically Skip Openings and Endings", isOn: Binding(
+            get: { model.openingEndingAutoSkip },
+            set: { model.setOpeningEndingAutoSkip($0) }))
+    }
+}
+
 @MainActor
 struct PlayerSponsorBlockMenu: View {
     @ObservedObject var model: PlayerModel
@@ -337,6 +348,7 @@ struct PlayerCommands: Commands {
                 }
             }
             PlayerMiruroMenu(model: model).disabled(!hasFocusedScene)
+            PlayerOpeningEndingSkipToggle(model: model)
             PlayerSponsorBlockMenu(model: model)
             Button(model.showsBufferInfo ? "Hide Buffer Info" : "Show Buffer Info") {
                 model.performMenuAction(bufferInfo)