feat: add comprehensive testing infrastructure

- Add Vitest for unit testing across all packages
- Add Playwright for E2E testing
- Add sample tests for API, Web, and Shared packages
- Configure Gitea Actions CI/CD workflows (ci, e2e, security, docker)
- Add testing documentation (TESTING.md)
- Add Gitea Actions setup guide
- Update .gitignore for test artifacts
- Add test environment configuration

package.json

@@ -10,6 +10,9 @@
     "dev": "npm run dev --workspaces --if-present",
     "build": "npm run build --workspaces --if-present",
     "test": "npm run test --workspaces --if-present",
+    "test:e2e": "playwright test",
+    "test:e2e:ui": "playwright test --ui",
+    "test:e2e:headed": "playwright test --headed",
     "lint": "npm run lint --workspaces --if-present",
     "docker:up": "docker-compose up -d",
     "docker:down": "docker-compose down",
@@ -17,5 +20,8 @@
   },
   "keywords": ["recipe", "cooking", "food", "manager"],
   "author": "",
-  "license": "MIT"
+  "license": "MIT",
+  "devDependencies": {
+    "@playwright/test": "^1.41.0"
+  }
 }