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/streaming/passthrough_test.cpp

@@ -0,0 +1,14 @@
+// Route: GET /streaming/passthrough
+#include "support/Assert.hpp"
+
+using namespace molo::example::test;
+
+int main() {
+  Fixture f;
+  auto res = f.client->get("/streaming/passthrough?target=/health");
+  check(res.status == 200, "status 200");
+  check(contains(res.body, "passthrough from /health"),
+        "upstream named");
+  check(contains(res.body, "\"status\":\"ok\""), "upstream body relayed");
+  return finish("streaming/passthrough");
+}