Add ScalarDB Analytics design doc

Author: josh-wong

versioned_sidebars/version-3.14-sidebars.json

@@ -148,6 +148,11 @@
               "id": "scalardb-cluster/getting-started-with-using-python-for-scalardb-cluster",
               "label": "Use Python for ScalarDB Cluster"
             },
+            {
+              "type": "doc",
+              "id": "scalardb-analytics/design",
+              "label": "ScalarDB Analytics Design"
+            },
             {
               "type": "doc",
               "id": "scalardb-analytics-postgresql/installation",