feat(auth): create register api call with basic test coverage and msw mock

src/features/auth/api/calls/register/register.mock.ts

@@ -0,0 +1,25 @@
+import { http, HttpResponse } from "msw";
+import type { AuthData } from "../../../model/types/service";
+import { BASE_URL } from "shared/config";
+import { REGISTER_API_ROUTE, MOCK_EMAIL, MOCK_TOKEN } from "./constants";
+
+const REGISTER_URL = `${BASE_URL}/${REGISTER_API_ROUTE}`;
+
+/**
+ * Msw interceptor. Mocks the register endpoint response.
+ */
+export const registerMock = http.post(REGISTER_URL, async ({ request }) => {
+  const { email } = (await request.json()) as AuthData;
+
+  if (email === MOCK_EMAIL) {
+    return HttpResponse.json(
+      { message: "User already exists" },
+      { status: 409 },
+    );
+  }
+
+  return HttpResponse.json({
+    accessToken: MOCK_TOKEN,
+    user: { id: "2", email },
+  });
+});