Fix crash with dataclasses that have __init_subclass__ modifying __init__

[Copilot]

This PR fixes a crash in pylint when processing dataclasses that use __init_subclass__ to modify the __init__ method. The issue occurred when inheriting from a generic dataclass without providing explicit type parameters.

Problem

When __init_subclass__ modifies the __init__ method by assignment (e.g., cls.__init__ = wrapped_init), astroid's dataclass brain module would crash with an AttributeError because it expected __init__ to always be a FunctionDef node, but after reassignment it becomes an AssignAttr node.

from dataclasses import dataclass
from typing import ParamSpec

@dataclass
class Foo[T]:
    def __init_subclass__(cls) -> None:
        cls.__init__ = wrap(cls.__init__)  # This causes the crash

@dataclass
class Bar(Foo): ...  # pylint crashes here

Solution

Added a monkey patch in pylint/checkers/dataclass_checker.py that replaces astroid's _find_arguments_from_base_classes function with a version that safely handles non-FunctionDef nodes. When __init__ has been modified by __init_subclass__, the patched function simply skips processing that base class rather than crashing.

The fix is minimal and surgical:

• Only affects the specific case where __init_subclass__ modifies __init__
• Preserves all existing dataclass functionality
• Gracefully handles edge cases like multiple inheritance and various assignment patterns

Testing

Added a comprehensive functional test (dataclass_generic_init_subclass.py) that verifies the fix works for both generic and non-generic dataclass inheritance scenarios. All existing dataclass and regression tests continue to pass.

Fixes #10519.

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[github-actions]

🤖 Effect of this PR on checked open source code: 🤖

Effect on home-assistant:
The following messages are no longer emitted:

1. import-private-name:
   Imported private module (_collections_abc)
   https://github.com/home-assistant/core/blob/1d2599184b49e53450b168c9c45627ac641adaa4/homeassistant/components/smlight/binary_sensor.py#L5

Effect on music21:
The following messages are now emitted:

1. invalid-name:
   Attribute name "id" doesn't conform to '[a-z_][A-Za-z0-9_]{2,30}$' pattern
   https://github.com/cuthbertLab/music21/blob/501e13d0058804471cbfba4b2d848971c86e7582/music21/prebase.py#L293
2. redefined-variable-type:
   Redefinition of sc3 type from music21.scale.MajorScale to music21.scale.MinorScale
   https://github.com/cuthbertLab/music21/blob/501e13d0058804471cbfba4b2d848971c86e7582/music21/scale/test_scale_main.py#L169

The following messages are no longer emitted:

1. invalid-name:
   Attribute name "id" doesn't conform to '[a-z_][A-Za-z0-9_]{2,30}$' pattern
   https://github.com/cuthbertLab/music21/blob/501e13d0058804471cbfba4b2d848971c86e7582/music21/base.py#L612
2. redefined-variable-type:
   Redefinition of sc3 type from music21.scale.MinorScale to music21.scale.MajorScale
   https://github.com/cuthbertLab/music21/blob/501e13d0058804471cbfba4b2d848971c86e7582/music21/scale/test_scale_main.py#L163

This comment was generated for commit aea77a1