Add VS Codium configuration.

.vscode/extensions.json

+{
+  // See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
+  // Extension identifier format: ${publisher}.${name}. Example: vscode.csharp
+
+  // List of extensions which should be recommended for users of this workspace.
+  "recommendations": [
+    "bradlc.vscode-tailwindcss",
+    "EditorConfig.EditorConfig",
+    "esbenp.prettier-vscode",
+    "svelte.svelte-vscode"
+  ],
+  // List of extensions recommended by VS Code that should not be recommended for users of this workspace.
+  "unwantedRecommendations": []
+}

.vscode/settings.json

+{
+  "editor.formatOnSave": true,
+  "[css]": {
+    "editor.defaultFormatter": "esbenp.prettier-vscode"
+  },
+  "[html]": {
+    "editor.defaultFormatter": "esbenp.prettier-vscode"
+  },
+  "[javascript]": {
+    "editor.defaultFormatter": "esbenp.prettier-vscode"
+  },
+  "[json]": {
+    "editor.defaultFormatter": "esbenp.prettier-vscode"
+  },
+  "[markdown]": {
+    "editor.defaultFormatter": "esbenp.prettier-vscode"
+  },
+  "[svelte]": {
+    "editor.defaultFormatter": "svelte.svelte-vscode"
+  }
+}