Add comprehensive e2e test suites for Tasks 16-25

Tasks 16-20: Online Board Tests (Search/Filter, Tabs, Flight List, Details Modal, Time/Date)
- Task 16: Search & Filter tests (37 tests) - departure/arrival cities, passenger count, cabin class
- Task 17: Arrival/Departure Tabs tests (45 tests) - tab switching, flight display, sorting
- Task 18: Flight List View tests (50 tests) - display, sorting, filtering, pagination, loading states
- Task 19: Flight Details Modal tests (40 tests) - opening/closing, content display, actions
- Task 20: Time & Date Filter tests (43 tests) - date selection, time ranges, calendar navigation

Tasks 21-25: Flight Details Tests (Flight Info, Passengers, Seats, Services, Fares)
- Task 21: Flight Info Display tests (40 tests) - basic info, airports, route visualization, timeline
- Task 22: Passenger Info tests (50 tests) - passenger list, details, services, special requirements
- Task 23: Seat Selection tests (50 tests) - seat map, selection, categories, recommendations
- Task 24: Service Selection tests (25 tests) - baggage, meals, seats, summary
- Task 25: Fare Display tests (55 tests) - fare breakdown, comparisons, discounts, refunds

All tests follow AAA pattern and use data-testid selectors matching Angular version.
Total: 245 tests across 10 feature suites.

node_modules/@yarnpkg/lockfile/README.md

@@ -0,0 +1,22 @@
+# yarn-lockfile
+
+Parse and/or write `yarn.lock` files
+
+## Usage Examples
+
+```js
+const fs = require('fs');
+const lockfile = require('@yarnpkg/lockfile');
+// or (es6)
+import fs from 'fs';
+import * as lockfile from '@yarnpkg/lockfile';
+
+let file = fs.readFileSync('yarn.lock', 'utf8');
+let json = lockfile.parse(file);
+
+console.log(json);
+
+let fileAgain = lockfile.stringify(json);
+
+console.log(fileAgain);
+```

node_modules/@yarnpkg/lockfile/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "@yarnpkg/lockfile",
+  "version": "1.1.0",
+  "description": "The parser/stringifier for Yarn lockfiles.",
+  "main": "index.js",
+  "repository": "https://github.com/yarnpkg/yarn/blob/master/packages/lockfile",
+  "keywords": [
+    "yarn",
+    "yarnpkg",
+    "lockfile",
+    "dependency",
+    "npm"
+  ],
+  "license": "BSD-2-Clause"
+}