feat: add cross-browser extension with AI reading assistant

- Create Pi Reader browser extension for Chrome/Firefox
- Chrome uses Side Panel API, Firefox uses Sidebar Action API
- Supports both browsers with separate manifests and unified codebase
- Built with mini-lit components and Tailwind CSS v4
- Features model selection dialog with Ollama support
- Hot reload development server watches both browser builds
- Add useDefineForClassFields: false to fix LitElement reactivity

tsconfig.base.json

@@ -15,6 +15,9 @@
 		"moduleResolution": "Node16",
 		"resolveJsonModule": true,
 		"allowImportingTsExtensions": false,
+		"experimentalDecorators": true,
+		"emitDecoratorMetadata": true,
+		"useDefineForClassFields": false,
 		"types": ["node"]
 	}
 }