DeskClock: Material Me? No YOU!

* Since Android 12 introduced a new style, try to mimic it for this app
* Due to AndroidX and the support libraries still being old, we have to,
  like Settings does with SettingsLib, create our own styles in the
  desired looks
* Also adjust the color scheme to reflect Material You
* We deviated from AOSP already quite a bit, so we don't need to really
  care about the change's footprint
* Clean up behind us by removing (now unused) resources and includes in
  files that were modified anyways (and adjust order while on it)
* Copy CollapsibleToolbarBaseActivity and required resources from
  SettingsLib - that way we can mimic the style easily without having
  to move this app to system_ext or using privileged_api
  * Since we always use dark layout, modify slightly so it works for us
  * Remove things we don't need so we don't have to copy too many files
    from SettingsLib

Change-Id: I4c81e03c71f468a9e468426a8233ad96059cb05d