chore: add extensions.json file for vscode

Author: urish

.vscode/extensions.json

@@ -0,0 +1,13 @@
+{
+  // See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
+
+  "recommendations": [
+    "editorconfig.editorconfig",
+    "esbenp.prettier-vscode",
+    "bierner.lit-html",
+    "dbaeumer.vscode-eslint"
+  ],
+
+  // List of extensions recommended by VS Code that should not be recommended for users of this workspace.
+  "unwantedRecommendations": []
+}