Implement comprehensive frontend integration testing with Playwright

- Add Playwright E2E testing framework with cross-browser support (Chrome, Firefox)
- Create authentication helpers for CalDAV server integration
- Implement calendar interaction helpers with event creation, drag-and-drop, and view switching
- Add comprehensive drag-and-drop test suite with event cleanup
- Configure CI/CD integration with Gitea Actions for headless testing
- Support both local development and CI environments with proper dependency management
- Include video recording, screenshots, and HTML reporting for test debugging
- Handle Firefox-specific timing and interaction challenges with force clicks and timeouts

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/e2e/tsconfig.json

@@ -0,0 +1,31 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "lib": ["ESNext", "DOM"],
+    "module": "commonjs",
+    "moduleResolution": "node",
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true,
+    "strict": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "declaration": false,
+    "outDir": "./dist",
+    "rootDir": ".",
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["./helpers/*"],
+      "@tests/*": ["./tests/*"]
+    }
+  },
+  "include": [
+    "tests/**/*",
+    "helpers/**/*",
+    "playwright.config.ts"
+  ],
+  "exclude": [
+    "node_modules",
+    "dist"
+  ]
+}