gh-142186: Allow all PEP-669 events to be per-code object and disableable (GH-146182)

* Make the `PY_UNWIND` monitoring event available as a code-local
event to allow trapping on function exit events when an exception
bubbles up. This complements the PY_RETURN event by allowing to
catch any function exit event.

* Allow `PY_UNWIND`  to be `DISABLE`d; disabling it disables the event for the whole code object.

* Do the above for `PY_THROW`, `RAISE`, `EXCEPTION_HANDLED`, and `RERAISE` events.