feat(api): add auth HTTP controller with tests

backend/tests/auth_http_test.cc

@@ -0,0 +1,53 @@
+#include <catch2/catch_test_macros.hpp>
+
+#include "csp/app_state.h"
+#include "csp/controllers/auth_controller.h"
+
+#include <drogon/HttpRequest.h>
+
+#include <future>
+
+namespace {
+
+drogon::HttpResponsePtr Call(
+    void (csp::controllers::AuthController::*fn)(
+        const drogon::HttpRequestPtr&,
+        std::function<void(const drogon::HttpResponsePtr&)>&&),
+    const Json::Value& body) {
+  auto req = drogon::HttpRequest::newHttpJsonRequest(body);
+  req->setMethod(drogon::Post);
+
+  std::promise<drogon::HttpResponsePtr> p;
+  csp::controllers::AuthController ctl;
+  (ctl.*fn)(req, [&p](const drogon::HttpResponsePtr& resp) { p.set_value(resp); });
+  return p.get_future().get();
+}
+
+}  // namespace
+
+TEST_CASE("auth controller: register + login") {
+  csp::AppState::Instance().Init(":memory:");
+
+  Json::Value reg;
+  reg["username"] = "bob";
+  reg["password"] = "password123";
+
+  auto regResp = Call(&csp::controllers::AuthController::registerUser, reg);
+  REQUIRE(regResp != nullptr);
+  REQUIRE(regResp->statusCode() == drogon::k200OK);
+  auto j1 = regResp->jsonObject();
+  REQUIRE(j1 != nullptr);
+  REQUIRE((*j1)["ok"].asBool() == true);
+  REQUIRE((*j1)["token"].asString().size() > 10);
+
+  Json::Value login;
+  login["username"] = "bob";
+  login["password"] = "password123";
+  auto loginResp = Call(&csp::controllers::AuthController::login, login);
+  REQUIRE(loginResp != nullptr);
+  REQUIRE(loginResp->statusCode() == drogon::k200OK);
+  auto j2 = loginResp->jsonObject();
+  REQUIRE(j2 != nullptr);
+  REQUIRE((*j2)["ok"].asBool() == true);
+  REQUIRE((*j2)["token"].asString().size() > 10);
+}