Optional fields in TypedDicts are not reported #18879

Bug Report
Optional fields in TypeDicts are not reported, allowing to unsafely access such fields.

To Reproduce

from typing import NotRequired, TypedDict


class Data(TypedDict):
    foo: NotRequired[int]


def extract(data: Data) -> int:
    return data["foo"]


print(extract({}))

https://mypy-play.net/?mypy=latest&python=3.12&flags=strict&gist=aa7bfac9b1c70873510bb3e28128f1d4

Expected Behavior
The code should raise a typing error similar to what pyright reports

mypy_typeddict.py:9:12 - error: Could not access item in TypedDict
    "foo" is not a required key in "Data", so access may result in runtime exception (reportTypedDictNotRequiredAccess)
1 error, 0 warnings, 0 informations

This is important because the code above does produce a runtime error.
Actual Behavior

No error is reported

Your Environment

• Mypy version used: 1.15.0
• Mypy command-line flags: --strict
• Mypy configuration options from mypy.ini (and other config files):
• Python version used: 3.12