CastDetailsView: Create CastDetailsViewModel and CastDetailsViewContent

Create the details view model and use it within CastTile. More
functionalities will be added to the view model in future CLs.

Bug: 378514236
Flag: com.android.systemui.qs_tile_detailed_view
Test: CastTileTest
Test: Click on cast tile in the QS -> go into details view instead of
showing the dialog.

Change-Id: I1e5357e1c92d5896a2ccba9036cfb8c0df393e6a