feat: add Playwright E2E tests for core user flows

[arbitask-ai]

Summary

Adds a complete Playwright E2E test suite for SoroSave frontend, addressing issue #1.

What was added

playwright.config.ts

• Configured with Chromium, Firefox, and Mobile Chrome (Pixel 5) projects
• WebServer auto-start for npm run dev
• CI-aware retry and worker settings

e2e/home.spec.ts — Landing page tests

• Hero heading renders correctly
• Brand name visible in navbar
• CTA buttons (Browse Groups, Create a Group) present
• "How It Works" section with all 4 steps
• "Why SoroSave?" feature cards
• Footer GitHub link

e2e/navigation.spec.ts — Navigation tests

• Navbar links navigate to correct pages
• CTA buttons navigate correctly
• Logo link returns to home
• Page title validation

e2e/group-creation.spec.ts — Form tests

• Form renders on /groups/new
• Submit validation triggers on empty form
• Name, contribution amount, and max members inputs accept correct values

e2e/wallet.spec.ts — Wallet connection tests (with mocked Freighter)

• Connect Wallet button visible in navbar
• Initial state shows "Connect" text
• Click triggers connection flow (mocked extension)

package.json — Added @playwright/test ^1.44.0 + test scripts

Running the tests

npm install
npx playwright install
npm run test:e2e

Closes #1

---

Submitted as part of the Algora bounty for #1

[arbitask-ai]

Hi! Just checking in on the Playwright E2E test suite. Tests cover 4 core flows across 3 browsers. Happy to add additional test cases or adjust the config if needed.