Fix table icons layout and add Qwen/MiniMax logos

Multiple graph and table improvements

Remove open/closed distinction from graph, use company logos as data points

Add company logos to graphs and tables, label frontier points with model names

Add category workflow diagrams for 5 OpenHands Index categories

Update UI: All-Hands-AI color scheme, agent version column names, and OpenHands logo

Replace AstaBench logo with OpenHands logo

Initial OpenHands Index leaderboard based on ASTA Bench