feat: centralize application framework primitives

packages/auth/test/engine.test.ts

@@ -4,6 +4,25 @@ import { MemoryAuthStore } from "../src/stores/memory.ts";
 import { generateTotp } from "../src/totp/index.ts";
 import type { AuthDeliveryMessage, PasskeyProvider } from "../src/types.ts";
 
+test("authentication storage factories resolve lazily and only once", async () => {
+  let calls = 0;
+  const backing = new MemoryAuthStore();
+  const engine = createAuthEngine({
+    store: () => {
+      calls++;
+      return backing;
+    },
+    secret: "a secure test secret that is longer than thirty-two characters",
+  });
+
+  expect(calls).toBe(0);
+  expect(engine.store).toBeDefined();
+  expect(calls).toBe(0);
+  await engine.getUser("missing");
+  await engine.getUser("still-missing");
+  expect(calls).toBe(1);
+});
+
 function fixture() {
   let time = 1_720_000_000_000;
   let seed = 11;