co-scientist-validatelisted

# co-scientist-validate Goal: - Validate one Co-Scientist run directory against the canonical artifact contracts. Expected input: - one run directory such as `runs/test1` Execution steps: 1. Run: ```bash python -m tools.validation.contract_validation <run-dir> --skill co-scientist-pipeline ``` 2. For resumed runs, include: ```bash --resume ``` 3. Report validation errors with artifact paths and issue messages. Rules: - This entry skill is a thin validation surface over `tools.validation.contract_validation`. - Do not declare a run valid without calling the validator.