Add new permission START_CROSS_PROFILE_ACTIVITIES

This allows holders of START_CROSS_PROFILE_ACTIVITIES permission to start an activity of the caller package in the other profile.
The "android.app.role.SYSTEM_WELLBEING" role will get this permission.

Test: atest CrossProfileAppsHostSideTest (with new tests in change I661d4b7132291950c8bcb4690d90154a78751b1e)
Ignore-AOSP-First: seeking internal review on WIP change prior to merging in AOSP
Change-Id: I4f368ec1a5facc0a95efee06b56522db853ff6d8
Bug: 207117478