fix feature: Track relationships between narrows of different variables #997

[asukaminato0721]

Summary

Fixes #997

This is an experiment.

Added guarded flow facts so if b == "bar": x = 3 records that x has the branch value when the same predicate is active again.

Applied matching guarded facts whenever narrowing ops are bound, recorded those facts from if branches and invalidated them on predicate/target reassignment.

Test Plan

Added regression test coverage for repeated predicates and predicate reassignment invalidation.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

dulwich (https://github.com/dulwich/dulwich)
+ ERROR dulwich/porcelain/subtree.py:324:34-49: Object of class `NoneType` has no attribute `id` [missing-attribute]

spark (https://github.com/apache/spark)
- ERROR python/pyspark/sql/tests/coercion/test_pandas_udf_input_type.py:73:21-23: `np` may be uninitialized [unbound-name]
- ERROR python/pyspark/sql/tests/coercion/test_pandas_udf_return_type.py:73:21-23: `np` may be uninitialized [unbound-name]
- ERROR python/pyspark/sql/tests/coercion/test_python_udf_input_type.py:73:21-23: `np` may be uninitialized [unbound-name]
- ERROR python/pyspark/sql/tests/coercion/test_python_udf_return_type.py:77:21-23: `np` may be uninitialized [unbound-name]
- ERROR python/pyspark/tests/upstream/pyarrow/test_pyarrow_array_cast.py:226:21-23: `np` may be uninitialized [unbound-name]

schemathesis (https://github.com/schemathesis/schemathesis)
+ ERROR src/schemathesis/openapi/checks.py:144:53-78: `in` is not supported between `str` and `Unresolvable` [not-iterable]
+ ERROR src/schemathesis/openapi/checks.py:144:53-78: `in` is not supported between `str` and `object` [not-iterable]
+ ERROR src/schemathesis/openapi/checks.py:146:38-61: Cannot index into `Unresolvable` [bad-index]
+ ERROR src/schemathesis/openapi/checks.py:146:38-61: Cannot index into `object` [bad-index]
+ ERROR src/schemathesis/openapi/checks.py:147:41-53: Object of class `Unresolvable` has no attribute `items`
+ Object of class `object` has no attribute `items` [missing-attribute]
+ ERROR src/schemathesis/openapi/checks.py:152:31-37: Argument `Unresolvable | bool | dict[str, Any] | dict[str, Unknown] | dict[Unknown, Unknown] | object` is not assignable to parameter `schema` with type `bool | dict[str, Any] | list[JsonSchema]` in function `schemathesis.core.jsonschema.bundler.unbundle` [bad-argument-type]

zulip (https://github.com/zulip/zulip)
+ ERROR zerver/views/auth.py:1013:41-50: Object of class `NoneType` has no attribute `url` [missing-attribute]

mypy (https://github.com/python/mypy)
- ERROR mypy/stubgenc.py:472:38-44: `output` may be uninitialized [unbound-name]
- ERROR mypy/stubtest.py:1288:9-17: `stub_sig` may be uninitialized [unbound-name]
- ERROR mypy/stubtest.py:1289:9-20: `runtime_sig` may be uninitialized [unbound-name]

sphinx (https://github.com/sphinx-doc/sphinx)
- ERROR sphinx/domains/cpp/__init__.py:1178:28-32: `decl` may be uninitialized [unbound-name]
+ ERROR sphinx/domains/cpp/__init__.py:1179:19-28: Object of class `NoneType` has no attribute `docname` [missing-attribute]

parso (https://github.com/davidhalter/parso)
- ERROR parso/python/tokenize.py:527:44-49: `token` may be uninitialized [unbound-name]