Copy pip surface for the usages outside transition

The surfaces in transition should be released once the transition
is finished. If the transition handler needs to perform some
actions to the surface outside the transition, it needs to make
a copy and manage when to release.

For pip1, the accesses outside transition use the surface from
PipTaskOrganizer#getSurfaceControl (not the leash from transition),
so only pip menu needs a copy for the case that uses the surface
from menu's surfaceCreated.

For pip2, all accesses use PipTransitionState#getPinnedTaskLeash.
So make a copy when receiving ENTERING_PIP and release the surface
when receiving EXITED_PIP.

Bug: 429548260
Flag: com.android.window.flags.release_all_transition_surfaces
Test: atest PinnedStackTests
Change-Id: I4889d168b99f370dfc865a00efe351ba89a1ec99