Add "stop playback" button to notification

app/src/main/java/org/jellyfin/android/RemotePlayerService.kt

@@ -276,6 +276,7 @@ class RemotePlayerService : Service(), CoroutineScope {
                 addAction(generateAction(R.drawable.ic_fast_forward_black_32dp, "Fast Forward", Constants.ACTION_FAST_FORWARD))
             }
             addAction(generateAction(R.drawable.ic_skip_next_black_32dp, "Next", Constants.ACTION_NEXT))
+            addAction(generateAction(R.drawable.ic_stop_black_32dp, "Stop", Constants.ACTION_STOP))
         }.build()
 
         // Post notification

app/src/main/res/drawable/ic_stop_black_32dp.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="32dp"
+    android:height="32dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#000000"
+        android:pathData="M6,6h12v12H6V6z" />
+</vector>