Add recommended extensions file for VSCode.

Author: HexDecimal

.editorconfig

@@ -22,3 +22,7 @@ indent_size = 2
 [*.{h,c,cpp}]
 indent_style = space
 indent_size = 2
+
+[*.json]
+indent_style = space
+indent_size = 4

.vscode/extensions.json

@@ -0,0 +1,17 @@
+{
+    // 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": [
+        "austin.code-gnu-global",
+        "editorconfig.editorconfig",
+        "ms-python.python",
+        "ms-python.vscode-pylance",
+        "ms-vscode.cpptools",
+        "redhat.vscode-yaml",
+        "tamasfe.even-better-toml",
+        "xaver.clang-format",
+    ],
+    // List of extensions recommended by VS Code that should not be recommended for users of this workspace.
+    "unwantedRecommendations": []
+}