refactor: nightly hardening - pydantic v2 config migration

[mouse-value-add]

Problem

PromptLens still used class-based Pydantic in key models. In Pydantic v2 this is deprecated and emits runtime warnings, increasing noise and future upgrade risk.

Approach

• Migrated model config declarations from class-based to in:
• Preserved behavior ( examples and for tool schemas).

Verification

• Ran test suite: ============================= test session starts ==============================
  platform darwin -- Python 3.9.6, pytest-8.4.2, pluggy-1.6.0
  rootdir: /Users/mouse/.openclaw/workspace/nightly/PromptLens
  configfile: pyproject.toml
  testpaths: tests
  plugins: anyio-4.12.1, asyncio-1.2.0, cov-7.1.0
  asyncio: mode=strict, debug=False, asyncio_default_fixture_loop_scope=None, asyncio_default_test_loop_scope=function
  collected 9 items

tests/test_cli_hardening.py ... [ 33%]
tests/test_http_provider_response_parsing.py .... [ 77%]
tests/test_loader_top_level_validation.py .. [100%]

=============================== warnings summary ===============================
../../../../Library/Python/3.9/lib/python/site-packages/google/api_core/_python_version_support.py:242
/Users/mouse/Library/Python/3.9/lib/python/site-packages/google/api_core/_python_version_support.py:242: FutureWarning: You are using a non-supported Python version (3.9.6). Google will not post any further updates to google.api_core supporting this Python version. Please upgrade to the latest Python version, or at least Python 3.10, and then update google.api_core.
warnings.warn(message, FutureWarning)

../../../../Library/Python/3.9/lib/python/site-packages/urllib3/init.py:35
/Users/mouse/Library/Python/3.9/lib/python/site-packages/urllib3/init.py:35: NotOpenSSLWarning: urllib3 v2 only supports OpenSSL 1.1.1+, currently the 'ssl' module is compiled with 'LibreSSL 2.8.3'. See: urllib3/urllib3#3020
warnings.warn(

../../../../Library/Python/3.9/lib/python/site-packages/google/auth/init.py:54
/Users/mouse/Library/Python/3.9/lib/python/site-packages/google/auth/init.py:54: FutureWarning: You are using a Python version 3.9 past its end of life. Google will update google-auth with critical bug fixes on a best-effort basis, but not with any other fixes or features. Please upgrade your Python version, and then update google-auth.
warnings.warn(eol_message.format("3.9"), FutureWarning)

../../../../Library/Python/3.9/lib/python/site-packages/google/oauth2/init.py:40
/Users/mouse/Library/Python/3.9/lib/python/site-packages/google/oauth2/init.py:40: FutureWarning: You are using a Python version 3.9 past its end of life. Google will update google-auth with critical bug fixes on a best-effort basis, but not with any other fixes or features. Please upgrade your Python version, and then update google-auth.
warnings.warn(eol_message.format("3.9"), FutureWarning)

promptlens/providers/google.py:8
/Users/mouse/.openclaw/workspace/nightly/PromptLens/promptlens/providers/google.py:8: FutureWarning:

All support for the google.generativeai package has ended. It will no longer be receiving
updates or bug fixes. Please switch to the google.genai package as soon as possible.
See README for more details:

https://github.com/google-gemini/deprecated-generative-ai-python/blob/main/README.md

import google.generativeai as genai

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
================================ tests coverage ================================
_______________ coverage: platform darwin, python 3.9.6-final-0 ________________

Name Stmts Miss Cover

promptlens/init.py 3 0 100%
promptlens/main.py 3 3 0%
promptlens/cli.py 169 120 29%
promptlens/exporters/init.py 6 0 100%
promptlens/exporters/base.py 15 5 67%
promptlens/exporters/csv_exporter.py 26 14 46%
promptlens/exporters/html_exporter.py 38 25 34%
promptlens/exporters/json_exporter.py 16 6 62%
promptlens/exporters/markdown_exporter.py 77 66 14%
promptlens/judges/init.py 3 0 100%
promptlens/judges/base.py 15 3 80%
promptlens/judges/llm_judge.py 71 50 30%
promptlens/judges/parser.py 107 97 9%
promptlens/judges/prompts.py 30 25 17%
promptlens/loaders/init.py 4 0 100%
promptlens/loaders/base.py 14 3 79%
promptlens/loaders/json_loader.py 23 8 65%
promptlens/loaders/yaml_loader.py 34 17 50%
promptlens/models/init.py 4 0 100%
promptlens/models/config.py 40 0 100%
promptlens/models/result.py 60 13 78%
promptlens/models/test_case.py 23 0 100%
promptlens/models/tools.py 73 34 53%
promptlens/providers/init.py 3 0 100%
promptlens/providers/anthropic.py 52 32 38%
promptlens/providers/base.py 23 6 74%
promptlens/providers/factory.py 21 10 52%
promptlens/providers/google.py 47 28 40%
promptlens/providers/http.py 67 26 61%
promptlens/providers/openai.py 57 36 37%
promptlens/providers/you.py 57 39 32%
promptlens/runners/init.py 2 0 100%
promptlens/runners/runner.py 96 74 23%
promptlens/utils/init.py 1 0 100%
promptlens/utils/cost.py 15 11 27%
promptlens/utils/diff.py 25 25 0%
promptlens/utils/retry.py 21 15 29%
promptlens/utils/timing.py 24 13 46%

TOTAL 1365 804 41%
Coverage HTML written to dir htmlcov
======================== 9 passed, 5 warnings in 1.07s =========================

• Result: 9 passed
• Confirmed Pydantic deprecation warnings related to class-based are removed.

Risks

• Low risk, this is a compatibility refactor with no intended behavior change.

Rollback Plan

• Revert this PR commit to restore previous model configuration style if any regression appears.