Add polymm project to README (#568)

Adds polymm under Prediction Markets.

polymm is an MIT-licensed Python market-making/arbitrage bot for
Polymarket sports and esports markets. It de-vigs sportsbook odds to
compute fair value, posts passive quotes, and hedges the opposite side.
Also includes wallet analytics scripts that run against any public
Polymarket wallet.

Full methodology and performance history:
https://kacho.io/open-sourcing-my-polymarket-bot
The wallet that ran it is public: https://polymarket.com/@b00k13

README has setup and usage examples. Repo is active and not archived.

README.md

@@ -553,6 +553,8 @@ A curated list of insanely awesome libraries, packages and resources for Quants
 - [marketlens](https://github.com/marketlenstrade/marketlens-python) - `Python` `MCP` - Tick-level Polymarket order book history with replay and a backtesting engine simulating queue priority, latency, and slippage.
 - [polymarket-bot-lab](https://github.com/oraclemangle/polymarket-bot-lab) - `Python` - Open-sourced research lab of 11 candidate Polymarket trading bots (weather, sports, longshot fades, maker, whale-flow) with a shared CLOB/backtest framework, ADR decision log, and honest paper/live results. Companion free dataset: [polymarket-canary-tape](https://huggingface.co/datasets/oraclemangle/polymarket-canary-tape) (300M+ events, CC-BY-4.0).
 - [Live Tennis API](https://livetennisapi.com) - `REST` `WebSocket` `MCP` - Real-time tennis scores, serving and break-point state, and model win probabilities for pricing tennis event markets, plus H2H, rankings and a 1968-2022 point-by-point archive; free tier. [GitHub](https://github.com/livetennisapi/livetennisapi-mcp)
+- [polymm](https://github.com/kachence/polymm) - `Python` `Polymarket` - Market-making and arbitrage bot for Polymarket sports and esports markets, pricing from de-vigged sportsbook odds.
+
 
 ## Calendars & Market Hours