Feature: Multiple ASCII art variants for monkeys

[wiertmir]

Goal

Provide multiple ASCII-art monkey variants and randomly pick one when showing monkey details to keep the UI fresh and fun.

Why

Small delight: different ASCII monkeys add personality each time a user inspects a monkey.

Light implementation notes

• Add a new Helpers/AsciiArtHelper.cs (or extend MonkeyHelper) that exposes IReadOnlyList<string> GetMonkeyArtVariants().
• Store each variant as a multi-line string literal (verbatim string @"...").
• When rendering monkey details, pick a random variant from the list and write it before the text details.
• Add unit test verifying the list contains >= 2 variants and variants render without throwing (basic smoke test).

Files to modify/create

• MyMonkeyApp/Helpers/AsciiArtHelper.cs
• (small change) MyMonkeyApp/Program.cs to call into the helper when printing details

Labels:["enhancement","feature-request","good first issue","area-console"]