fix(android): use window display metrics for dp <-> px conversion in PixelUtil

PixelUtil is the dp <-> px conversion the layout engine uses. Reading
the screen display metrics returns the primary display's density, which
is incorrect when the activity is on a secondary display (Samsung DeX,
desktop windowing, virtual displays via am start --display N). The
resulting density mismatch makes Fabric lay out content at the wrong
scale, leaving the visible region clipped to a fraction of the activity
window and rendering text at sub-pixel positions.

Reverts the four call sites changed in #53523 back to
getWindowDisplayMetrics, restoring 0.81 behaviour on secondary displays.
Single-display behaviour is unchanged because window and screen metrics
match in that case.

Fixes #56894 (relates to #55659).

Changelog: [ANDROID] [FIXED] - Use window display metrics in PixelUtil so layout scales correctly on secondary displays / desktop mode / freeform windows.

Author: DouweBos

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/PixelUtil.kt

@@ -22,7 +22,7 @@ public object PixelUtil {
     return TypedValue.applyDimension(
         TypedValue.COMPLEX_UNIT_DIP,
         value,
-        DisplayMetricsHolder.getScreenDisplayMetrics(),
+        DisplayMetricsHolder.getWindowDisplayMetrics(),
     )
   }
 
@@ -40,7 +40,7 @@ public object PixelUtil {
       return Float.NaN
     }
 
-    val displayMetrics = DisplayMetricsHolder.getScreenDisplayMetrics()
+    val displayMetrics = DisplayMetricsHolder.getWindowDisplayMetrics()
     val scaledValue = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, value, displayMetrics)
 
     if (maxFontScale >= 1) {
@@ -63,13 +63,13 @@ public object PixelUtil {
       return Float.NaN
     }
 
-    return value / DisplayMetricsHolder.getScreenDisplayMetrics().density
+    return value / DisplayMetricsHolder.getWindowDisplayMetrics().density
   }
 
   /** @return [Float] that represents the density of the display metrics for device screen. */
   @JvmStatic
   public fun getDisplayMetricDensity(): Float =
-      DisplayMetricsHolder.getScreenDisplayMetrics().density
+      DisplayMetricsHolder.getWindowDisplayMetrics().density
 
   /* Kotlin extensions */
   public fun Int.dpToPx(): Float = toPixelFromDIP(this.toFloat())