Challenge 2: Rewriting With an Explicit Main — Possible Solution
====================================================================

Program.cs (explicit form):

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Hello from my first C# program!");
        Console.WriteLine("This file has no class or Main at all.");
    }
}

Terminal:

    dotnet run

Output:

    Hello from my first C# program!
    This file has no class or Main at all.

Explanation:
Both versions produce byte-for-byte identical output. The explicit
form spells out exactly what the top-level-statement version from
Challenge 1 compiles down to automatically: a class named Program
containing a static void Main(string[] args) method, with the same
two Console.WriteLine calls inside its body. Neither version is more
"correct" -- top-level statements are real sugar over this exact
shape, not a different execution model.

WHY THIS WORKS AS AN ANSWER
------------------------------
This reproduces Challenge 1's output using the explicit class/Main
form the chapter shows as top-level statements' compiled-down
equivalent, confirming they're genuinely the same program written two
different ways, exactly as the chapter states.