fix(16): add async/await to createTestDb in route and MCP tests

Route and MCP test files were calling createTestDb() without await,
causing db to be a Promise object instead of a Drizzle instance.
Also rewrote auth route tests for OIDC-based auth (merge picked old version).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/routes/params.test.ts

@@ -6,8 +6,8 @@ import { setupRoutes } from "../../src/server/routes/setups";
 import { threadRoutes } from "../../src/server/routes/threads";
 import { createTestDb } from "../helpers/db";
 
-function createTestApp() {
-	const { db, userId } = createTestDb();
+async function createTestApp() {
+	const { db, userId } = await createTestDb();
 	const app = new Hono();
 	app.use("*", async (c, next) => {
 		c.set("db", db);
@@ -24,8 +24,8 @@ function createTestApp() {
 describe("Invalid ID parameter handling", () => {
 	let app: Hono;
 
-	beforeEach(() => {
-		app = createTestApp();
+	beforeEach(async () => {
+		app = await createTestApp();
 	});
 
 	describe("items", () => {