[Dual Shade] Define dynamic colors for the shade header chips.

Also, reduce the horizontal paddings to 6dp per the latest UX spec.

Bug: 397223606
Test: Unit tests still pass.
Test: Manually by opening the notifications shade and quick settings
 shades and observing the colors appear as expected.
Flag: com.android.systemui.scene_container
Change-Id: I4a250c7fba9c795cf0d16c5851a3417236f4d721