test(connect): update oauth-scope tests for server-side nonce state format

Update the connect-route test harness in oauth-scope.test.ts to match the
new state format: state now carries only a 64-char hex nonce, with userId
stored server-side in Redis. Add a Redis mock to buildConnectApp so the
callback route can look up the userId during tests.

Author: Ridanshi

apps/backend/src/__tests__/oauth-scope.test.ts

@@ -38,14 +38,25 @@ const USER_ID = 'user-scope-test';
 
 // ── Connect-route test harness ────────────────────────────────────────────────
 
-function makeConnectState(userId: string): string {
-  return Buffer.from(JSON.stringify({ userId, nonce: 'test-nonce' })).toString('base64');
+// 64 lowercase hex chars — matches the format generated by randomBytes(32).toString('hex')
+const TEST_NONCE = 'a'.repeat(64);
+
+function makeConnectState(_userId: string): string {
+  // State carries only the nonce; userId is stored server-side in Redis.
+  return TEST_NONCE;
 }
 
-function buildConnectApp(mockPrisma: Partial<PrismaClient>) {
+function buildConnectApp(mockPrisma: Partial<PrismaClient>, userId = USER_ID) {
+  const mockRedis = {
+    get: vi.fn().mockResolvedValue(JSON.stringify({ userId })),
+    del: vi.fn().mockResolvedValue(1),
+    set: vi.fn().mockResolvedValue('OK'),
+  };
+
   const app = Fastify({ logger: false });
   app.decorate('prisma', mockPrisma as PrismaClient);
-  app.decorate('authenticate', async (req: any) => { req.user = { id: USER_ID }; });
+  app.decorate('redis', mockRedis as any);
+  app.decorate('authenticate', async (req: any) => { req.user = { id: userId }; });
   app.register(connectRoutes, { prefix: '/api/connect' });
   return app.ready().then(() => app);
 }