Python 3.14 compatibility: replace pydantic.v1 imports in _base_compat.py

[clemlesne]

Problem

On Python 3.14 (including free-threaded 3.14t), importing zhipuai emits:

/zhipuai/core/_base_compat.py:48: UserWarning: Core Pydantic V1 functionality isn't compatible with Python 3.14 or greater.
  from pydantic.v1.typing import (

Pydantic has officially stated that pydantic.v1 is not supported on Python 3.14+. This is currently a warning but will likely break in a future pydantic release.

Root cause

zhipuai/core/_base_compat.py lines 48-55 import from pydantic.v1 when pydantic v2 is detected:

if PYDANTIC_V2:
    from pydantic.v1.typing import (
        get_args as get_args,
        is_union as is_union,
        get_origin as get_origin,
        is_typeddict as is_typeddict,
        is_literal_type as is_literal_type,
    )
    from pydantic.v1.datetime_parse import parse_date as parse_date, parse_datetime as parse_datetime

Suggested fix

All these functions have stdlib equivalents available since Python 3.8-3.12:

pydantic.v1 import	stdlib replacement
get_args	typing.get_args
get_origin	typing.get_origin
is_union	typing.get_origin(tp) is Union or isinstance(tp, types.UnionType)
is_literal_type	typing.get_origin(tp) is Literal
is_typeddict	typing.is_typeddict (3.12+) or typing_extensions.is_typeddict
parse_date / parse_datetime	manual parsing or dateutil.parser

This is the only file in the package that references pydantic.v1.

Environment

• Python 3.14t (free-threaded)
• pydantic 2.12.5
• zhipuai 2.1.5.20250825