add vscode intellisense

.vscode/c_cpp_properties.json

@@ -0,0 +1,12 @@
+{
+    "configurations": [
+        {
+            "name": "Linux",
+            "defines": [],
+            "cStandard": "c17",
+            "cppStandard": "c++17",
+            "compileCommands": ".vscode/compile_commands.json"
+        }
+    ],
+    "version": 4
+}