Virtually split WMShellSmokeTestsDesktopMode module

This CL splits the WMShellSmokeTestsDesktopMode module into two; one for
projected mode (supported on phone) and the other for extended mode
(supported on tablet and desktop), which allows granular configuration
in its TEST_MAPPING while keeping better compatibility with the infra.

Flag: EXEMPT TEST_ONLY
Bug: 444316017
Test: atest WMShellSmokeTestsDesktopMode-ProjectedMode
Test: atest WMShellSmokeTestsDesktopMode-ExtendedMode
Change-Id: I8339bb0857db5b8df5496dc9975c4e5b5a6710da