Add e2e test suite from flights-front with Angular API mocks

Copies Playwright e2e tests (58 specs, 300+ tests) designed for cross-app
testing. Adapts API mocks to match real Aeroflot dictionary format (title
objects with multilingual keys), adds board/schedule/days endpoint mocks,
and provides Angular-specific Playwright config on port 4203.

playwright-angular.config.ts

@@ -0,0 +1,42 @@
+import { defineConfig, devices } from '@playwright/test';
+
+/**
+ * Playwright config for running e2e tests against the Angular app only.
+ * Angular runs on port 4203 with NODE_OPTIONS=--openssl-legacy-provider.
+ */
+export default defineConfig({
+  testDir: './tests/e2e-angular',
+  fullyParallel: true,
+  forbidOnly: !!process.env.CI,
+  retries: process.env.CI ? 2 : 0,
+  workers: process.env.CI ? 1 : undefined,
+  reporter: [['html', { outputFolder: 'playwright-report-angular' }]],
+  outputDir: 'test-results-angular',
+  timeout: 45_000,
+  use: {
+    trace: 'on-first-retry',
+    navigationTimeout: 15_000,
+  },
+  expect: {
+    timeout: 15_000,
+    toHaveScreenshot: {
+      maxDiffPixelRatio: 0.05,
+    },
+  },
+  projects: [
+    {
+      name: 'angular-ru-ru',
+      use: {
+        ...devices['Desktop Chrome'],
+        baseURL: 'http://localhost:4203',
+        locale: 'ru-ru',
+      },
+    },
+  ],
+  webServer: {
+    command: 'cd ClientApp && NODE_OPTIONS=--openssl-legacy-provider npx ng serve --port 4203',
+    url: 'http://localhost:4203',
+    reuseExistingServer: true,
+    timeout: 120_000,
+  },
+});