Eagerly initialized per display SystemUIDisplaySubcomponent upon adding a display

Problem:
Previously, the SystemUI display repository created per-display instances on-demand. However, components like the wallpaper presentation require these instances to exist proactively to update the keyguard for secondary display.

Changes:
1. This change introduces a new field to create per-display components eagerly upon display addition, resolving the above problem.
2. Addresses a bug in WallpaperPresentation where we only hide the presentation instead of dismiss it.

Flag: com.android.window.flags.enable_connected_displays_wallpaper_presentations
Bug: 441940469
Test: atest CtsMediaProjectionTestCases:MediaProjectionTest
Test: atest CtsWindowManagerDeviceKeyguard:MultiDisplayKeyguardTests
Test: atest SystemUITests:PerDisplayInstanceRepositoryImplTest
Test: atest SystemUITests:WallpaperPresentationManagerTest
Test: atest SystemUITests:PhoneStatusBarViewControllerTest
Change-Id: I125489126e2fb5c20a8c0649a606129792a0a09b