Add independent validation suite and API runner

MANIFEST.in

@@ -3,3 +3,4 @@ include scripts/check_wheel_install.py
 include CHANGELOG.md
 recursive-include docs *.md
 recursive-include examples *.json
+include scripts/validate_independent.py

docs/independent-validation.md

@@ -0,0 +1,32 @@
+# Independent synthetic validation
+
+30 authored cases, unrelated to Machina: 16 objective, 6 ambiguous/invalid and
+8 adversarial. Choice, Score and Noul have explicit rules and labels fixed before
+live calls. The deterministic baseline gets 30/30; it is the reference rule
+implementation, not independent human validation or evidence that AI adds value.
+The model should match these rules. Perfect accuracy here does not establish
+real-world accuracy, safety, calibration or resistance to arbitrary injection.
+Do not tune prompts against these cases and continue calling them held out.
+
+From a repository checkout, with the provider key already configured:
+
+```bash
+python -m pip install -e .
+python scripts/validate_independent.py
+python scripts/validate_independent.py --provider gemini --output independent-report.json
+```
+
+Replace gemini with groq or openai to use the corresponding environment variable.
+Use --model to select a model explicitly. Do not commit or paste credentials.
+The offline command makes no API calls. The live command attempts 30 evaluations,
+each with up to 3 HTTP attempts and a 35-second evaluation budget. Provider usage
+may be billed; no second model or repetitions are run automatically.
+
+The JSON contains individual answers, accuracy, group counts, failures, review
+counts, successful latency p50/p95, token coverage, model/configuration, dataset
+hashes and Git commit. Exit 1 indicates a wrong answer or failed request; setup
+errors also terminate unsuccessfully. Investigate each error instead of masking
+it with aggregate accuracy. Compare independent reports for another provider only
+when needed. Never mistake an offline baseline result for model performance.
+
+No live result is included: the preparation environment has no supported API key.