Ensure dialogs from Quick Settings are always visible on the focused display

Previously, when a dialog was launched from a Quick Settings (QS) tile outside of the notification shade (e.g., from the all-apps list), it was incorrectly parented to the shade window. This caused the dialog to be invisible until the shade was pulled down.

This change ensures that such dialogs are opened on the currently focused display and are not parented to the shade. This allows the dialog to be visible immediately, regardless of the shade's status.

Note: While e2e tests cover QS dialogs opened from the shade, test coverage for the all-apps scenario is still needed.

Bug: 423929154
Flag: NONE - fix for broken functionality to cp on release branch
Test: OpenInternetQSDialogOnOtherDisplay, OpenQSBluetoothDialogOnOtherDisplay, OpenQSModesDialogOnOtherDisplay
Change-Id: I35320b667954dd2833221562423f04fb33ced259