gorisanson/quoridor-ai — reverse-engineered prompt

Build me a simple browser game where I can play Quoridor against an AI. I want the normal 9x9 board, two pawns, wall placement, legal move checking, and the real rule that walls can never block every path to the goal. Please include the usual pawn movement rules, including straight jumps and diagonal jumps when they are actually allowed. Show whose turn it is, how many walls each player has left, and make it easy to restart a game.

The main point is the computer opponent. I want it to use Monte Carlo tree search and feel meaningfully stronger across a few difficulty levels like Novice, Average, Good, and Strong. It is fine if stronger levels think longer. If you need to, look up the Quoridor rules online to make sure edge cases are correct.

Please make the AI play reasonably smart, especially with wall placement near pawns and existing walls, and make the whole thing usable as a small web app I can run locally and play in the browser.