feat: add element-inspector

- Implemented Rulers component for zoom/pan-aware rulers on canvas.
- Created Stage component to serve as a zoomable and pannable viewport for the device frame.
- Developed Toolbar component for responsive controls, including device presets and zoom functionalities.
- Introduced useFrame composable to manage iframe interactions and inspections.
- Established a reactive store to manage application state, including guides and viewport dimensions.
- Added utility functions for color parsing and box model calculations.
- Integrated Tailwind CSS for styling and improved scrollbar aesthetics.
- Implemented unit tests for color utilities and rectangle calculations.
- Configured TypeScript and Vite for the project setup.

element-inspector/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "extends": "@vue/tsconfig/tsconfig.dom.json",
+  "compilerOptions": {
+    "jsxImportSource": "vue-jsx-vapor",
+    "types": ["chrome", "node", "vite/client"],
+    "noUncheckedIndexedAccess": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true
+  },
+  "include": ["src", "vite.config.ts", "*.d.ts"]
+}