e2e-testing

# E2E Testing Patterns Comprehensive Playwright patterns for building stable, fast, and maintainable E2E test suites. ## Test File Organization ``` tests/ ├── e2e/ │ ├── auth/ │ │ ├── login.spec.ts │ │ ├── logout.spec.ts │ │ └── register.spec.ts │ ├── features/ │ │ ├── browse.spec.ts │ │ ├── search.spec.ts │ │ └── create.spec.ts │ └── api/ │ └── endpoints.spec.ts ├── fixtures/ │ ├── auth.ts │ └── data.ts └── playwright.config.ts ``` ## Page Object Model (POM) ```typescript import { Page, Locator } from '@playwright/test' export class ItemsPage { readonly page: Page readonly searchInput: Locator readonly itemCards: Locator readonly createButton: Locator constructor(page: Page) { this.page = page this.searchInput = page.locator('[data-testid="search-input"]') this.itemCards = page.locator('[data-testid="item-card"]') this.createButton = page.locator('[data-testid="create-btn"]') } async goto() { await this.page.goto('/items') await this.page.waitForLoadState('networkidle') } async search(query: string) { await this.searchInput.fill(query) await this.page.waitForResponse(resp => resp.url().includes('/api/search')) await this.page.waitForLoadState('networkidle') } async getItemCount() { return await this.itemCards.count() } } ``` ## Test Structure ```typescript import { test, expect } from '@playwright/test' import { ItemsPage } from '../../pages/ItemsPage' test.de...