feat: add compose deliverable, scenario definitions, eval stub, and CI

eval/run_eval.py

@@ -0,0 +1,23 @@
+"""Eval harness entry point.
+
+Fixture mode (default, key-free): byte-snapshots of deterministic pipeline
+stages against recorded cassettes. Live mode: property assertions only —
+LLM output is constrained, not pinned.
+"""
+
+from pathlib import Path
+
+import yaml
+
+SCENARIOS_FILE = Path(__file__).parent / "scenarios.yaml"
+
+
+def load_scenarios() -> dict:
+    """Load the shared scenario definitions."""
+    with SCENARIOS_FILE.open() as handle:
+        return yaml.safe_load(handle)
+
+
+if __name__ == "__main__":
+    scenarios = load_scenarios()
+    print(f"{len(scenarios['scenarios'])} scenarios, {len(scenarios['refinements'])} refinements")