test: add Dockerized E2E test environment with Playwright + Mailpit (#860)

e2e/playwright.config.ts

@@ -0,0 +1,28 @@
+import { defineConfig, devices } from '@playwright/test';
+
+const WORKER_BASE = process.env.WORKER_URL!;
+const FRONTEND_BASE = process.env.FRONTEND_URL!;
+
+export default defineConfig({
+  timeout: 30_000,
+  retries: 0,
+  workers: 1,
+  reporter: [['html', { open: 'never' }]],
+  projects: [
+    {
+      name: 'api',
+      testDir: './tests/api',
+      use: {
+        baseURL: WORKER_BASE,
+      },
+    },
+    {
+      name: 'browser',
+      testDir: './tests/browser',
+      use: {
+        baseURL: FRONTEND_BASE,
+        ...devices['Desktop Chrome'],
+      },
+    },
+  ],
+});