use different description strings for screen attention settings and contextual card

1. Revert the screen attention description string to the old approved
string.
2. Create a new summary string for 'Screen Attention' contextual slice.
3. Fix some character issues.
Bug: 134457354
Bug: 134585794
Test: make RunSettingsRoboTests -j 32
Change-Id: I401fc6707203790e51aed8738b4658c6a30f512e