feat: nightly hardening - HTTP plain-text response fallback

[mouse-value-add]

Problem

Some HTTP model endpoints return successful plain-text bodies instead of JSON. The HTTP provider currently assumes JSON and raises a content-type parsing error, producing avoidable failed runs.

Approach

• Added a content-type fallback path in .
• If JSON parsing fails with , it now reads the response as text and uses that as model output.
• Added a focused unit test to verify plain-text extraction behavior.

Verification

• Ran ============================= 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 10 items

tests/test_cli_hardening.py ... [ 30%]
tests/test_http_provider_response_parsing.py ..... [ 80%]
tests/test_loader_top_level_validation.py .. [100%]

=============================== warnings summary ===============================
promptlens/models/tools.py:14
/Users/mouse/.openclaw/workspace/nightly/PromptLens/promptlens/models/tools.py:14: PydanticDeprecatedSince20: Support for class-based config is deprecated, use ConfigDict instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.12/migration/
class ToolParameter(BaseModel):

promptlens/models/test_case.py:10
/Users/mouse/.openclaw/workspace/nightly/PromptLens/promptlens/models/test_case.py:10: PydanticDeprecatedSince20: Support for class-based config is deprecated, use ConfigDict instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.12/migration/
class TestCase(BaseModel):

promptlens/models/test_case.py:66
/Users/mouse/.openclaw/workspace/nightly/PromptLens/promptlens/models/test_case.py:66: PydanticDeprecatedSince20: Support for class-based config is deprecated, use ConfigDict instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.12/migration/
class GoldenSet(BaseModel):

promptlens/models/config.py:100
/Users/mouse/.openclaw/workspace/nightly/PromptLens/promptlens/models/config.py:100: PydanticDeprecatedSince20: Support for class-based config is deprecated, use ConfigDict instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.12/migration/
class RunConfig(BaseModel):

../../../../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 41 0 100%
promptlens/models/result.py 60 13 78%
promptlens/models/test_case.py 25 0 100%
promptlens/models/tools.py 74 34 54%
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 75 30 60%
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 1377 808 41%
Coverage HTML written to dir htmlcov
======================== 10 passed, 9 warnings in 1.09s ========================.

• Result: 10 passed.

Risks

• Plain-text fallback may return non-model text for misconfigured endpoints. This is still safer than hard-failing valid text responses.

Rollback plan

• Revert this PR commit to restore strict JSON-only parsing behavior in the HTTP provider.