feat: scaffold C++ template with tooling helpers

src/main.cpp

@@ -0,0 +1,14 @@
+#include <iostream>
+#include <vector>
+#include <string>
+#include <algorithm>
+#include <numeric>
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    // TODO: Add program logic here.
+
+    return 0;
+}