feat(stats): add migration v7 visit table and client-ip helpers

tests/test_web_server.py

@@ -75,7 +75,7 @@ def test_readonly_routes_and_static():
             assert status == 200 and payload["ok"] is True
             status, _, payload = running.json("/api/about")
             assert status == 200
-            assert payload["data"]["schema_version"] == 6
+            assert payload["data"]["schema_version"] == 7
             assert payload["data"]["analytics"]["min_duration_seconds"] == 600
 
             status, _, overview = running.json("/api/overview")