🚚(frontend) delete useless nesting

Update frontend to be the root folder of the frontend sources,
instead of nesting them in a folder named as the application.

We only work on a single frontend app as of today, nesting
sources doesn't add any value, even though the initial organization
was more extensible.

src/frontend/package.json

@@ -0,0 +1,31 @@
+{
+  "name": "visio",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "tsc -b && vite build",
+    "lint": "eslint . --ext ts,tsx --report-unused-disable-directives --max-warnings 0",
+    "preview": "vite preview"
+  },
+  "dependencies": {
+    "react": "18.2.0",
+    "react-dom": "18.2.0"
+  },
+  "devDependencies": {
+    "@types/react": "18.3.3",
+    "@types/react-dom": "18.3.0",
+    "@typescript-eslint/eslint-plugin": "7.13.1",
+    "@typescript-eslint/parser": "7.13.1",
+    "@vitejs/plugin-react": "4.3.1",
+    "eslint": "8.57.0",
+    "eslint-plugin-react-hooks": "4.6.2",
+    "eslint-plugin-react-refresh": "0.4.7",
+    "typescript": "5.5.2",
+    "vite": "5.3.1",
+    "@livekit/components-react": "2.3.3",
+    "@livekit/components-styles": "1.0.12",
+    "livekit-client": "2.3.1"
+  }
+}