This is a follow-up PR for #156000.
In this PR we add the ability to signal pass failures
(`signal_pass_failure()`) in python-defined passes.
To achieve this, we expose `MlirExternalPass` via `nb::class_` with a
method `signal_pass_failure()`, and the callable passed to `pm.add(..)`
now accepts two arguments (`op: MlirOperation, pass_:
MlirExternalPass`).
For example:
```python
def custom_pass_that_fails(op, pass_):
if some_condition:
pass_.signal_pass_failure()
# do something
```
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