Update storage wizard to latest UX mocks.

Mostly shuffling around strings and layouts.  Slow device warning is
now a full-screen activity, and format warning is now a dialog.

Bug: 76097999
Test: atest com.android.settings.ui.StorageWizardTest
Change-Id: Ifd74e3b1389f0cc9590f6a6a2cd49671f3bbc746