Add a pytest-discovered tests/conftest.py for the last30days scripts path and
remove duplicate per-file sys.path.insert boilerplate from tests.
Normalize affected imports to rely on the shared scripts path and remove the
now-unneeded E402 suppressions.
The Gemini 3.1 Flash Lite preview model is being discontinued on
May 25, 2026. Per Google's GA announcement, the underlying model
architecture is identical and only the model identifier needs to
be updated from `gemini-3.1-flash-lite-preview` to
`gemini-3.1-flash-lite`.
Also relaxes the `_require_gemini_31_preview` guard to accept any
`gemini-3.1-*` identifier (renamed to `_require_gemini_31`), so the
GA name and the still-preview `gemini-3.1-pro-preview` both pass.
The second assertion in test_resolve_google_judge_api_key_prefers_google_key
ran outside the mock.patch.dict context. When GOOGLE_API_KEY or GEMINI_API_KEY
is set in the real environment, os.environ takes precedence over the config
dict fallback and the test fails.
Wrap the assertion in its own mock.patch.dict scope that clears the three
relevant env vars so the test passes regardless of the developer's env.
This contribution was developed with AI assistance (Claude Code).
Yong-yuan-X