Minor cleanup

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderViewModel.kt

@@ -798,9 +798,9 @@ class ReaderViewModel(
         Error,
     }
 
-    sealed class SaveImageResult {
-        class Success(val uri: Uri) : SaveImageResult()
-        class Error(val error: Throwable) : SaveImageResult()
+    sealed interface SaveImageResult {
+        class Success(val uri: Uri) : SaveImageResult
+        class Error(val error: Throwable) : SaveImageResult
     }
 
     /**
@@ -860,18 +860,18 @@ class ReaderViewModel(
             get() = viewerChapters?.currChapter?.pages?.size ?: -1
     }
 
-    sealed class Dialog {
-        data object Loading : Dialog()
-        data object Settings : Dialog()
-        data class PageActions(val page: ReaderPage) : Dialog()
+    sealed interface Dialog {
+        data object Loading : Dialog
+        data object Settings : Dialog
+        data class PageActions(val page: ReaderPage) : Dialog
     }
 
-    sealed class Event {
-        data object ReloadViewerChapters : Event()
-        data class SetOrientation(val orientation: Int) : Event()
-        data class SetCoverResult(val result: SetAsCoverResult) : Event()
+    sealed interface Event {
+        data object ReloadViewerChapters : Event
+        data class SetOrientation(val orientation: Int) : Event
+        data class SetCoverResult(val result: SetAsCoverResult) : Event
 
-        data class SavedImage(val result: SaveImageResult) : Event()
-        data class ShareImage(val uri: Uri, val page: ReaderPage) : Event()
+        data class SavedImage(val result: SaveImageResult) : Event
+        data class ShareImage(val uri: Uri, val page: ReaderPage) : Event
     }
 }

app/src/main/java/eu/kanade/tachiyomi/ui/reader/model/ReaderChapter.kt

@@ -39,10 +39,10 @@ data class ReaderChapter(val chapter: Chapter) {
         }
     }
 
-    sealed class State {
-        data object Wait : State()
-        data object Loading : State()
-        data class Error(val error: Throwable) : State()
-        data class Loaded(val pages: List<ReaderPage>) : State()
+    sealed interface State {
+        data object Wait : State
+        data object Loading : State
+        data class Error(val error: Throwable) : State
+        data class Loaded(val pages: List<ReaderPage>) : State
     }
 }