Coding Challenge idea: Circle the Cat

There's a great old turn-based Flash game called Circle the Cat.

https://www.google.co.uk/search?q=circle+the+cat

The Cat starts in the middle of a hexagonal grid and you have to build a wall of circles to stop it from escaping. Each game starts with randomly pre-placed circles and the game ends either when the cat escapes off the edge or you have managed to successfully trap it.

The issue names no repository files, tests, or entry points; start by reviewing the linked Circle the Cat reference and the stated hexagonal-grid rules. Done would mean a turn-based implementation with random pre-placed circles, wall-building play, and the described escape or trapping outcomes.

Written by the indexing model from the issue text.