mach: Support raising EXCEPTION_*_IDENTITY_PROTECTED

This is a follow-up to 226847ab2f143ffeb51822ed0cc39d358614c727, which
added server-side support for EXCEPTION_STATE_IDENTITY_PROTECTED.
This change implements client-side and server-side support for raising,
receiving, and forwarding both EXCEPTION_STATE_IDENTITY_PROTECTED and
EXCEPTION_IDENTITY_PROTECTED exceptions via UniversalExceptionRaise()
and UniversalMachExcServer.

This is required to allow unit testing of the protected exception paths
in exc_client_variants_test, and to support future forwarding of Mach
exceptions to original handlers in the iOS crash handler on iOS 18+.

Bug: 401232341
Change-Id: I6b6fd63cfa9d32f93b9bb05901811a085c2d72b7
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/7736788
Commit-Queue: Justin Cohen <justincohen@google.com>
Reviewed-by: Mark Mentovai <mark@chromium.org>