generic dataclass with default (and typevar default)

Bug Report

this is the sameish as #12962 however now that PEP 696 exists I expect this to work

To Reproduce

from typing import Literal
from dataclasses import dataclass

@dataclass
class D[TBool: (Literal[True], Literal[False]) = Literal[True]]:
    val: TBool = True


reveal_type(D())
reveal_type(D(True))
reveal_type(D(False))

Expected Behavior

I expect no errors however

Actual Behavior

t3.py:6: error: Incompatible types in assignment (expression has type "Literal[True]", variable has type "TBool")  [assignment]
t3.py:9: note: Revealed type is "t3.D[Literal[True]]"
t3.py:10: note: Revealed type is "t3.D[Literal[True]]"
t3.py:11: note: Revealed type is "t3.D[Literal[False]]"
Found 1 error in 1 file (checked 1 source file)

(the reveal types are all correct -- mostly just to demonstrate that the idea works)

Your Environment

• Mypy version used: 1.15.0
• Mypy command-line flags: n/a
• Mypy configuration options from mypy.ini (and other config files): n/a
• Python version used: 3.13.0

Start by running the supplied reproduction with mypy 1.15.0 on Python 3.13.0 and compare the assignment error with the three reveal_type results. Trace the dataclass generic and type-variable-default handling implicated by the example; done means the assignment is accepted while all three revealed types remain as shown.