[bc25] Adjust the shade width based on the screen width.

This CL uses tentative values based on current UX mocks. Once final
specs are received they will be adjusted accordingly.

Test: Manually tested by opening the notifications shade on a foldable
device both in a folded and unfolded configuration.
Test: Unit tests build and pass.
Bug: 337849926
Flag: com.android.systemui.dual_shade

Change-Id: I2c6ade7e13fbc7dcba28a787f198f0de628adb9a