Add VSCode configuration files for debugging and building with CMake; refactor main.cpp to clean up includes

.vscode/launch.json

@@ -0,0 +1,16 @@
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Debug",
+            "type": "lldb",
+            "request": "launch",
+            "program": "${command:cmake.launchTargetPath}",
+            "args": [],
+            // CHANGE THIS LINE:
+            // Point the working directory to the folder containing the executable
+            "cwd": "${command:cmake.launchTargetDirectory}",
+            "preLaunchTask": "CMake: build"
+        }
+    ]
+}