feat: add cucumber gherkin-style E2E test framework

- Install @cucumber/cucumber and cucumber-pretty dependencies
- Create Cucumber configuration with tsx loader for TypeScript support
- Add step definitions for common navigation, form interactions, and assertions
- Add authentication step definitions for login/logout flows
- Create feature files for user registration and authentication
- Support multiple auth contexts (player, tournament admin, club admin)
- Configure package.json scripts for running Cucumber tests

Key features:
- Gherkin syntax (Given/When/Then) for behavior-driven testing
- Browser-only interactions (no direct database access)
- Dev site testing (tests run against running dev server)
- Happy path focus for acceptance testing
- Integration with existing TypeScript project

package.json

@@ -15,6 +15,9 @@
     "test:unit:sequential": "bun test src/__tests__/unit/ --max-concurrency=1",
     "test:acceptance": "bun x playwright test e2e/",
     "test:acceptance:headed": "bun x playwright test e2e/ --headed",
+    "test:acceptance:cucumber": "bun cucumber-js --config e2e/cucumber/cucumber.config.ts",
+    "test:acceptance:cucumber:pretty": "bun cucumber-js --config e2e/cucumber/cucumber.config.ts --format pretty:cucumber-pretty",
+    "cucumber": "bun cucumber-js --config e2e/cucumber/cucumber.config.ts",
     "db:switch": "bun run scripts/switch-database.js",
     "db:setup-postgres": "bun run scripts/setup-postgres.js",
     "db:setup-dev": "bun run scripts/setup-postgres.js",
@@ -59,6 +62,7 @@
     "zod": "^4.3.6"
   },
   "devDependencies": {
+    "@cucumber/cucumber": "^12.8.2",
     "@playwright/test": "^1.58.2",
     "@tailwindcss/postcss": "^4",
     "@testing-library/jest-dom": "^6.9.1",
@@ -74,10 +78,12 @@
     "@types/react-dom": "^19.2.3",
     "@vitejs/plugin-react": "^6.0.1",
     "argon2": "^0.44.0",
+    "cucumber-pretty": "^6.0.1",
     "eslint": "^8.57.0",
     "eslint-config-next": "^16.2.1",
     "jsdom": "^29.0.1",
     "tailwindcss": "^4",
+    "tsx": "^4.21.0",
     "typescript": "^5",
     "vitest": "^4.1.2"
   }