Finish the NestJS migration — drop the legacy Express app

NestJS now serves the whole surface: every /api domain plus the platform
routes (uploads, /mcp, the OAuth/MCP SDK + /.well-known metadata and the
production SPA fallback). Removed server/src/app.ts, all of
server/src/routes/* and the strangler dispatcher; index.ts and the
integration suite share a single buildApp() bootstrap so prod and tests
can't drift.

- Platform/transport routes extracted to nest/platform/platform.routes.ts
  and mounted before app.init() — Nest's router answers an unmatched
  request with a 404, so a route registered after init is never reached.
  The SPA fallback is a NotFoundException filter and the catch-all uses a
  RegExp (Express 5's path-to-regexp rejects a bare '*').
- New modules: memories (/api/integrations/memories — the Journey
  gallery's Immich/Synology proxy), addons (GET /api/addons) and the
  cross-trip GET /api/reservations/upcoming.
- TrekExceptionFilter reproduces the old multer / err.statusCode handling
  so upload rejections keep their 400/413 { error } body and non-ASCII
  filenames survive (defParamCharset).
- addTripToJourney and the MCP get_journey_share_link tool gained the
  trip-access check they were missing.
- Re-pointed the 34 integration tests + the websocket test onto the Nest
  app; removed the now-meaningless Express-vs-Nest parity tests and a few
  orphaned client components.

server/tests/websocket/connection.test.ts

@@ -39,27 +39,31 @@ vi.mock('../../src/config', () => ({
   JWT_SECRET: 'test-jwt-secret-for-trek-testing-only',
   ENCRYPTION_KEY: 'a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6a7b8c9d0e1f2a3b4c5d6a7b8c9d0e1f2',
   updateJwtSecret: () => {},
+  DEFAULT_LANGUAGE: 'en',
 }));
 
-import { createApp } from '../../src/app';
+import type { INestApplication } from '@nestjs/common';
+import { buildApp } from '../../src/bootstrap';
 import { createTables } from '../../src/db/schema';
 import { runMigrations } from '../../src/db/migrations';
-import { resetTestDb } from '../helpers/test-db';
+import { resetTestDb, resetRateLimits } from '../helpers/test-db';
 import { createUser, createTrip } from '../helpers/factories';
 import { authCookie } from '../helpers/auth';
-import { loginAttempts, mfaAttempts } from '../../src/routes/auth';
 import { setupWebSocket } from '../../src/websocket';
 import { createEphemeralToken } from '../../src/services/ephemeralTokens';
 
 let server: http.Server;
 let wsUrl: string;
+let nestApp: INestApplication;
 
 beforeAll(async () => {
   createTables(testDb);
   runMigrations(testDb);
 
-  const app = createApp();
-  server = http.createServer(app);
+  // Real WebSocket against the unified NestJS app (Express is gone). buildApp owns
+  // the same composition production uses; we attach the real ws server to it.
+  nestApp = await buildApp();
+  server = http.createServer(nestApp.getHttpAdapter().getInstance());
   setupWebSocket(server);
 
   await new Promise<void>(resolve => server.listen(0, resolve));
@@ -71,13 +75,13 @@ afterAll(async () => {
   await new Promise<void>((resolve, reject) =>
     server.close(err => err ? reject(err) : resolve())
   );
+  await nestApp.close();
   testDb.close();
 });
 
 beforeEach(() => {
   resetTestDb(testDb);
-  loginAttempts.clear();
-  mfaAttempts.clear();
+  resetRateLimits(nestApp);
 });
 
 /** Buffered WebSocket wrapper that never drops messages. */