use layout_weight instead of maxWidth; fix RTL margin

- Replace marginRight with marginEnd to support RTL
- Avoid hard max width; use layout_width=0 + layout_weight to adapt to screen sizes
- Add length limit guard for track title to prevent overflow

Author: Ljn0626

app/src/main/java/org/schabi/newpipe/player/ui/MainPlayerUi.java

@@ -289,6 +289,7 @@ protected void setupElementsVisibility() {
         binding.topControls.setClickable(true);
         binding.topControls.setFocusable(true);
 
+        binding.metadataView.setVisibility(isFullscreen ? View.VISIBLE : View.GONE);
         binding.titleTextView.setVisibility(isFullscreen ? View.VISIBLE : View.GONE);
         binding.channelTextView.setVisibility(isFullscreen ? View.VISIBLE : View.GONE);
     }
@@ -934,6 +935,7 @@ public void toggleFullscreen() {
         }
         fragmentListener.onFullscreenStateChanged(isFullscreen);
 
+        binding.metadataView.setVisibility(isFullscreen ? View.VISIBLE : View.GONE);
         binding.titleTextView.setVisibility(isFullscreen ? View.VISIBLE : View.GONE);
         binding.channelTextView.setVisibility(isFullscreen ? View.VISIBLE : View.GONE);
         binding.playerCloseButton.setVisibility(isFullscreen ? View.GONE : View.VISIBLE);

app/src/main/res/layout/player.xml

@@ -160,12 +160,15 @@
 
                     <org.schabi.newpipe.views.NewPipeTextView
                         android:id="@+id/audioTrackTextView"
-                        android:layout_width="wrap_content"
+                        android:layout_width="0dp"
                         android:layout_height="35dp"
                         android:layout_marginEnd="8dp"
+                        android:layout_weight="1"
                         android:background="?attr/selectableItemBackground"
                         android:gravity="center"
                         android:minWidth="0dp"
+                        android:singleLine="true"
+                        android:ellipsize="end"
                         android:padding="@dimen/player_main_buttons_padding"
                         android:textColor="@android:color/white"
                         android:textStyle="bold"