android: Add drop shadow to FPS counter

Also let the style control the text size

src/android/app/src/main/res/layout/fragment_emulation.xml

@@ -139,7 +139,7 @@
 
             <com.google.android.material.textview.MaterialTextView
                 android:id="@+id/show_fps_text"
-                style="@style/TextAppearance.Material3.BodyMedium"
+                style="@style/TextAppearance.Material3.BodySmall"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_gravity="left"
@@ -147,7 +147,8 @@
                 android:focusable="false"
                 android:paddingHorizontal="20dp"
                 android:textColor="@android:color/white"
-                android:textSize="12sp"
+                android:shadowColor="@android:color/black"
+                android:shadowRadius="3"
                 tools:ignore="RtlHardcoded" />
 
         </FrameLayout>