improve mute/subscribe buttons in AccountActivity (#4762)

Regression from the Material 3 redesign.

The background behind the buttons was not extending all the way up like
it should. Also make the subscribe button larger and the outline better
to see in the dark theme.

Before / After:

<img
src="https://github.com/user-attachments/assets/aa530d62-182c-48fd-b2d3-f7386ea4d909"
width="300"/> <img
src="https://github.com/user-attachments/assets/534f9a7c-2832-433b-a529-c72ee260b9cf"
width="300"/>

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

@@ -46,6 +46,7 @@
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
                     android:layout_marginTop="180dp"
+                    android:background="?attr/colorSurface"
                     android:paddingStart="16dp"
                     android:paddingEnd="16dp">
 
@@ -80,11 +81,11 @@
                         android:layout_height="0dp"
                         android:layout_marginStart="16dp"
                         android:layout_marginEnd="6dp"
-                        android:minWidth="0dp"
-                        android:paddingStart="8dp"
-                        android:paddingEnd="4dp"
-                        android:scaleType="centerInside"
+                        android:minWidth="36dp"
+                        android:paddingStart="12dp"
+                        android:paddingEnd="12dp"
                         app:icon="@drawable/ic_notifications_24dp"
+                        app:iconPadding="0dp"
                         app:layout_constrainedHeight="true"
                         app:layout_constraintBottom_toBottomOf="@+id/accountFollowButton"
                         app:layout_constraintEnd_toStartOf="@id/accountFollowButton"
@@ -100,11 +101,11 @@
                         android:layout_height="0dp"
                         android:layout_marginStart="16dp"
                         android:layout_marginEnd="6dp"
-                        android:minWidth="0dp"
-                        android:paddingStart="8dp"
-                        android:paddingEnd="8dp"
-                        android:scaleType="centerInside"
+                        android:minWidth="36dp"
+                        android:paddingStart="12dp"
+                        android:paddingEnd="12dp"
                         app:icon="@drawable/ic_unmute_24dp"
+                        app:iconPadding="0dp"
                         app:layout_constrainedHeight="true"
                         app:layout_constraintBottom_toBottomOf="@+id/accountFollowButton"
                         app:layout_constraintEnd_toStartOf="@id/accountSubscribeButton"

app/src/main/res/values-night/theme_colors.xml

@@ -19,7 +19,7 @@
 
     <color name="iconColor">@color/tusky_grey_70</color>
 
-    <color name="colorBackgroundAccent">@color/tusky_grey_30</color>
+    <color name="colorBackgroundAccent">@color/tusky_grey_40</color>
     <color name="colorBackgroundHighlight">@color/tusky_grey_50</color>
     <color name="dividerColor">@color/tusky_grey_40</color>
     <color name="dividerColorOther">@color/tusky_grey_10</color>