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/webdav/files_test.cpp

@@ -0,0 +1,23 @@
+// Route: /webdav/files/  (PROPFIND, GET, PUT, DELETE)
+#include "support/Assert.hpp"
+
+using namespace molo::example::test;
+using molo::example::fw::Method;
+
+int main() {
+  Fixture f;
+  auto list = f.client->request(Method::Propfind, "/webdav/files/");
+  check(list.status == 207, "propfind is 207");
+  check(contains(list.body, "welcome.txt"), "seed file listed");
+  auto put = f.client->request(Method::Put, "/webdav/files/new.txt",
+                               "new-data", {{"Content-Type", "text/plain"}});
+  check(put.status == 201, "put is 201");
+  auto get = f.client->request(Method::Get, "/webdav/files/new.txt");
+  check(contains(get.body, "new-data"), "round trip works");
+  auto del =
+      f.client->request(Method::Delete, "/webdav/files/new.txt");
+  check(del.status == 200, "delete is 200");
+  auto gone = f.client->request(Method::Get, "/webdav/files/new.txt");
+  check(gone.status == 404, "deleted file is 404");
+  return finish("webdav/files");
+}