fix(msgspec): handle boolean tz constraint from Meta

[tysoncung]

Problem

When using msgspec.Meta(tz=True) with a datetime field, polyfactory crashes with a TypeError because handle_constrained_date receives a bool for the tz parameter but expects a tzinfo object.

Closes #768

Reproduction

from datetime import datetime
from typing import Annotated

from msgspec import Struct, Meta
from polyfactory.factories.msgspec_factory import MsgspecFactory


class SomeStruct(Struct):
    some_datetime: Annotated[datetime, Meta(tz=True)]


class SomeStructFactory(MsgspecFactory[SomeStruct]): ...

SomeStructFactory.build()  # TypeError!

Solution

In handle_constrained_date, convert boolean tz values before using them:

• True → timezone.utc (timezone-aware datetime)
• False → None (falls back to UTC default)

This is a minimal, targeted fix in polyfactory/value_generators/constrained_dates.py.

Changes

File	Change
polyfactory/value_generators/constrained_dates.py	Update tz type hint to accept bool, convert boolean values before use