[A11y] Notification Intelligence Feedback UI

1. Set adjustment status in content descriptions for different feedback indicators
2. Enlarge feedback icon size

Bug: 175657733
Bug: 175662413
Test: atest com.android.systemui.statusbar.notification, manually test
on device

Change-Id: I6ca0fbc625555d1849d1b4a2749d182434f9f3d2