gh-161242: Use AC vectorcall for AttributeError, ImportError, NameError (#161462)

These exceptions and their subclasses had no vectorcall, and `__init__`
parsed keywords through PyArg_ParseTupleAndKeywords with a temporary
empty tuple on every call.  Error messages are unchanged except when more
keywords than parameters are given, which now names the unexpected
keyword.

The clinic inputs have no docstring, so docstrings are unchanged and
these exceptions don't gain a `__text_signature__`.

pyperf microbenchmark (PGO+LTO, run serially):

| Benchmark                        | base    | vectorcall            |
|----------------------------------|:-------:|:---------------------:|
| AttributeError(s, name=s, obj=s) | 127 ns  | 41.9 ns: 3.02x faster |
| ImportError(s, name=s, path=s)   | 129 ns  | 43.4 ns: 2.96x faster |
| NameError(s, name=s)             | 88.3 ns | 39.3 ns: 2.24x faster |
| ModuleNotFoundError(s, name=s)   | 89.9 ns | 40.6 ns: 2.21x faster |
| AttributeError(s)                | 39.4 ns | 32.1 ns: 1.23x faster |
| UnboundLocalError(s)             | 38.6 ns | 31.8 ns: 1.22x faster |
| NameError(s)                     | 38.5 ns | 32.2 ns: 1.19x faster |
| ImportError(s)                   | 40.7 ns | 34.4 ns: 1.18x faster |
| attribute_error_to_none()        | 176 ns  | 173 ns: 1.02x faster  |

Benchmark code:

```python
import pyperf

runner = pyperf.Runner()
setup = """s = 'x'
class O: pass
o = O()
def attribute_error_to_none():
    try:
        o.x
    except AttributeError:
        pass
"""
for stmt in ["AttributeError(s)", "AttributeError(s, name=s, obj=s)",
             "NameError(s)", "NameError(s, name=s)",
             "ImportError(s)", "ImportError(s, name=s, path=s)",
             "ModuleNotFoundError(s, name=s)", "UnboundLocalError(s)",
             "attribute_error_to_none()"]:
    runner.timeit(stmt, stmt, setup)
```

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: cmaloney

Lib/test/test_call.py

@@ -208,7 +208,7 @@ def test_varargs14_kw(self):
                                itertools.product, 0, repeat=1, foo=2)
 
     def test_varargs15_kw(self):
-        msg = r"^ImportError\(\) takes at most 3 keyword arguments \(4 given\)$"
+        msg = r"^ImportError\(\) got an unexpected keyword argument 'foo'$"
         self.assertRaisesRegex(TypeError, msg,
                                ImportError, 0, name=1, path=2, name_from=3, foo=3)
 

Misc/NEWS.d/next/Core_and_Builtins/2026-11-06-21-21-04.gh-issue-161242.d4vNgC.rst

@@ -0,0 +1,3 @@
+Speed up :exc:`AttributeError`, :exc:`ImportError` and
+:exc:`NameError` by enabling :ref:`vectorcall`. Unexpected
+keyword arguments are now reported by name.