feat(ui): add dedicated station search fragment for television platforms

app/src/main/res/layout-television/dialog_add_station.xml

@@ -11,6 +11,7 @@
         android:layout_height="0dp"
         android:clipToPadding="false"
         android:paddingBottom="16dp"
+        android:nextFocusRight="@id/dialog_negative_button"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toStartOf="@+id/guideline"
         app:layout_constraintStart_toStartOf="parent"
@@ -39,6 +40,7 @@
             style="@style/Widget.Material3.Button"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            android:nextFocusLeft="@id/station_list"
             android:text="@string/dialog_find_station_button_add" />
 
         <Button
@@ -47,6 +49,7 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginTop="12dp"
+            android:nextFocusLeft="@id/station_list"
             android:text="@string/dialog_generic_button_cancel" />
 
     </LinearLayout>