feat: implement MoloApp plans 01-15 with integration

Full C++23 framework tree: runtime, observability, security,
data, app, realtime, supervisor, clients, CLI, example plus
enterprise tenancy, audit, operability, governance,
supplychain. Postgres via docker compose for tests.

example/fw/TestClient.hpp

@@ -0,0 +1,38 @@
+#pragma once
+
+// Test client: drives the real Application (routing, middleware, views, DI,
+// error mapping, in-memory DB) without sockets, plus a cookie jar and frozen
+// time hook. Gap: real test client in 08-clients-openapi.md owns fixtures,
+// DB resets, and time freezing.
+
+#include <map>
+#include <memory>
+#include <string>
+
+#include "App.hpp"
+
+namespace molo::example::fw {
+
+class TestClient {
+ public:
+  explicit TestClient(std::shared_ptr<Application> app);
+
+  Response get(const std::string& path);
+  Response post(const std::string& path, const std::string& body = "",
+                const std::string& content_type = "text/plain");
+  Response request(Method method, const std::string& path,
+                   const std::string& body = "",
+                   const std::map<std::string, std::string>& headers =
+                       {});
+
+  void freeze_time(const std::string& iso);
+  const std::string& frozen_time() const;
+  void clear_cookies();
+
+ private:
+  std::shared_ptr<Application> app_;
+  std::map<std::string, std::string> jar_;
+  std::string frozen_time_;
+};
+
+}  // namespace molo::example::fw