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.

tests/example/pubsub/publish_test.cpp

@@ -0,0 +1,20 @@
+// Route: /pubsub/publish
+#include "support/Assert.hpp"
+
+using namespace molo::example::test;
+
+int main() {
+  Fixture f;
+  int seen = 0;
+  f.services.pubsub->subscribe("news",
+                               [&](const std::string&) { ++seen; });
+  auto pub = f.client->post("/pubsub/publish",
+                            "{\"topic\":\"news\",\"message\":\"hi\"}",
+                            "application/json");
+  check(pub.status == 200, "publish status 200");
+  check(contains(pub.body, "\"delivered\":1"), "one subscriber reached");
+  check(seen == 1, "side effect: listener ran");
+  auto hist = f.client->get("/pubsub/publish?topic=news");
+  check(contains(hist.body, "hi"), "history kept");
+  return finish("pubsub/publish");
+}