feat: add devcontainer configuration (VoltAgent#658)

* feat: add devcontainer configuration for TypeScript and Node.js environment

* feat: update devcontainer configuration with VSCode customizations and onCreateCommand

* fix: format devcontainer.json for consistency

Author: sakkeam

.devcontainer/devcontainer.json

@@ -0,0 +1,10 @@
+{
+  "image": "mcr.microsoft.com/devcontainers/typescript-node:22",
+  "customizations": {
+    "vscode": {
+      "extensions": ["biomejs.biome", "esbenp.prettier-vscode"]
+    }
+  },
+  // https://github.com/pnpm/pnpm/issues/5803#issuecomment-1360641459
+  "onCreateCommand": "pnpm config set store-dir /home/node/.local/share/pnpm/store && pnpm install"
+}