feat(dotnet): add domain parity artifact gate

tests/unit/test_validate_dotnet_domain_parity_artifact_v1.py

@@ -0,0 +1,39 @@
+from __future__ import annotations
+
+import json
+import subprocess
+import sys
+from pathlib import Path
+
+
+def test_validate_dotnet_domain_parity_artifact_passes() -> None:
+    root = Path(__file__).resolve().parents[2]
+    temp = root / "Temp" / "dotnet_domain_parity_v1.json"
+    temp.write_text('{"gate":"PASS","total":44,"passed":44}', encoding="utf-8")
+
+    proc = subprocess.run(
+        [sys.executable, str(root / "tools" / "validate_dotnet_domain_parity_artifact_v1.py")],
+        cwd=root,
+        capture_output=True,
+        text=True,
+    )
+    assert proc.returncode == 0, proc.stdout + proc.stderr
+    payload = json.loads(proc.stdout)
+    assert payload["gate"] == "PASS"
+
+
+def test_validate_dotnet_domain_parity_artifact_reports_bad_total() -> None:
+    root = Path(__file__).resolve().parents[2]
+    temp = root / "Temp" / "test_dotnet_domain_parity_bad.json"
+    temp.write_text('{"gate":"PASS","total":39,"passed":39}', encoding="utf-8")
+
+    proc = subprocess.run(
+        [sys.executable, str(root / "tools" / "validate_dotnet_domain_parity_artifact_v1.py"), "--artifact", str(temp)],
+        cwd=root,
+        capture_output=True,
+        text=True,
+    )
+    assert proc.returncode != 0
+    payload = json.loads(proc.stdout)
+    assert payload["gate"] == "FAIL"
+    assert "total" in payload["missing"]