When the preference loads, initialize the slider position using the
cursor area size value from settings.
In addition, match slider seekbar range and the cursor area size range.
Change-Id: Ib6a8ca8463358a3e2de5ae6be8afd5113a5826be
Bug: b/383901288
Test: ToggleAutoclickCursorAreaSizeControllerTest
Flag: com.android.server.accessibility.enable_autoclick_indicator