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/exponential-backoff/src/delay/always/always.delay.spec.ts

@@ -0,0 +1,65 @@
+import { AlwaysDelay } from "./always.delay";
+import { IBackOffOptions, getSanitizedOptions } from "../../options";
+
+describe(AlwaysDelay.name, () => {
+  let options: IBackOffOptions;
+  let delay: AlwaysDelay;
+
+  function initClass() {
+    delay = new AlwaysDelay(options);
+  }
+
+  beforeEach(() => {
+    options = getSanitizedOptions({});
+    initClass();
+    jest.useFakeTimers();
+  });
+
+  it(`when calling #apply, the delay is equal to the starting delay`, async () => {
+    const spy = jest.fn();
+    delay.apply().then(spy);
+    jest.runTimersToTime(options.startingDelay);
+    await Promise.resolve();
+
+    expect(spy).toHaveBeenCalledTimes(1);
+  });
+
+  it(`when the attempt number is 1, when calling #apply,
+  the delay is equal to the starting delay multiplied by the time multiple`, async () => {
+    delay.setAttemptNumber(1);
+
+    const spy = jest.fn();
+    delay.apply().then(spy);
+    jest.runTimersToTime(options.startingDelay * options.timeMultiple);
+    await Promise.resolve();
+
+    expect(spy).toHaveBeenCalledTimes(1);
+  });
+
+  it(`when the attempt number is 2, when calling #apply,
+  the delay is equal to the starting delay multiplied by the time multiple raised by the attempt number`, async () => {
+    const attemptNumber = 2;
+    delay.setAttemptNumber(attemptNumber);
+
+    const spy = jest.fn();
+    delay.apply().then(spy);
+    jest.runTimersToTime(
+      options.startingDelay * Math.pow(options.timeMultiple, attemptNumber)
+    );
+    await Promise.resolve();
+
+    expect(spy).toHaveBeenCalledTimes(1);
+  });
+
+  it(`when the #maxDelay is less than #startingDelay, when calling #apply,
+  the delay is equal to the #maxDelay`, async () => {
+    options.maxDelay = options.startingDelay - 1;
+
+    const spy = jest.fn();
+    delay.apply().then(spy);
+    jest.runTimersToTime(options.maxDelay);
+    await Promise.resolve();
+
+    expect(spy).toHaveBeenCalledTimes(1);
+  });
+});

node_modules/exponential-backoff/src/delay/always/always.delay.ts

@@ -0,0 +1,3 @@
+import { Delay } from "../delay.base";
+
+export class AlwaysDelay extends Delay {}

node_modules/exponential-backoff/src/delay/delay.base.ts

@@ -0,0 +1,34 @@
+import { IDelay } from "./delay.interface";
+import { IBackOffOptions } from "../options";
+import { JitterFactory } from "../jitter/jitter.factory";
+
+export abstract class Delay implements IDelay {
+  protected attempt = 0;
+  constructor(private options: IBackOffOptions) {}
+
+  public apply() {
+    return new Promise(resolve => setTimeout(resolve, this.jitteredDelay));
+  }
+
+  public setAttemptNumber(attempt: number) {
+    this.attempt = attempt;
+  }
+
+  private get jitteredDelay() {
+    const jitter = JitterFactory(this.options);
+    return jitter(this.delay);
+  }
+
+  private get delay() {
+    const constant = this.options.startingDelay;
+    const base = this.options.timeMultiple;
+    const power = this.numOfDelayedAttempts;
+    const delay = constant * Math.pow(base, power);
+
+    return Math.min(delay, this.options.maxDelay);
+  }
+
+  protected get numOfDelayedAttempts() {
+    return this.attempt;
+  }
+}

node_modules/exponential-backoff/src/delay/delay.factory.ts

@@ -0,0 +1,18 @@
+import { IBackOffOptions } from "../options";
+import { SkipFirstDelay } from "./skip-first/skip-first.delay";
+import { AlwaysDelay } from "./always/always.delay";
+import { IDelay } from "./delay.interface";
+
+export function DelayFactory(options: IBackOffOptions, attempt: number): IDelay {
+    const delay = initDelayClass(options);
+    delay.setAttemptNumber(attempt);
+    return delay;
+}
+
+function initDelayClass(options: IBackOffOptions) {
+    if (!options.delayFirstAttempt) {
+        return new SkipFirstDelay(options);
+    }
+
+    return new AlwaysDelay(options);
+}

node_modules/exponential-backoff/src/delay/delay.interface.ts

@@ -0,0 +1,4 @@
+export interface IDelay {
+  apply: () => Promise<unknown>;
+  setAttemptNumber: (attempt: number) => void;
+}

node_modules/exponential-backoff/src/delay/skip-first/skip-first.delay.ts

@@ -0,0 +1,15 @@
+import { Delay } from "../delay.base";
+
+export class SkipFirstDelay extends Delay {
+    public async apply() {
+        return this.isFirstAttempt ? true : super.apply();
+    }
+
+    private get isFirstAttempt() {
+        return this.attempt === 0;
+    }
+
+    protected get numOfDelayedAttempts() {
+        return this.attempt - 1;
+    }
+}