feat: add stage 0 foundation

backend/apps/audit/tests/__init__.py

@@ -0,0 +1 @@
+

backend/apps/audit/tests/test_audit_api.py

@@ -0,0 +1,20 @@
+from apps.audit.models import OperationAuditLog
+
+
+def test_list_operation_logs_returns_recent_logs(client, db):
+    OperationAuditLog.objects.create(
+        module="system",
+        action="health_check",
+        target_type="system",
+        target_id="health",
+        result="success",
+        request_snapshot={"path": "/api/system/health"},
+    )
+
+    response = client.get("/api/audit/operation-logs")
+
+    assert response.status_code == 200
+    payload = response.json()
+    assert len(payload) == 1
+    assert payload[0]["module"] == "system"
+    assert payload[0]["action"] == "health_check"