chore: add vscode launcher for mocha debugging

.vscode/launch.json

@@ -0,0 +1,32 @@
+{
+  // Use IntelliSense to learn about possible attributes.
+  // Hover to view descriptions of existing attributes.
+  // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "type": "node",
+      "request": "launch",
+      "name": "Launch Program",
+      "skipFiles": [
+        "<node_internals>/**"
+      ],
+      "program": "${workspaceFolder}\\index.js"
+    }, {
+      "name": "Mocha: Current File",
+      "type": "node",
+      "request": "launch",
+      "program": "${workspaceFolder}/node_modules/mocha/bin/_mocha",
+      "args": [
+        "-s 0",
+        "--file",
+        "${relativeFile}",
+        "--no-timeout"
+      ],
+      "console": "integratedTerminal",
+      "skipFiles": [
+        "<node_internals>/**"
+      ]
+    }
+  ]
+}