Expand Speedrun Stylus with AI Reviews and New Challenges

Speedrun Stylus grew to ~750 users, 250 active builders, and 810 challenge submissions across 14 tracks. The Foundation Challenge (ERC20) has 110 submissions. DeFi Vibekit challenges 11-13 focus on AI-powered agents. LLM-based code reviews now score code 0-100. Smart Cache CLI boosts Arbitrum Sepolia deployments. Radar scans Rust contracts for vulnerabilities. 29% connect GitHub. Funded by Arbitrum DAO.