fix(xychart): auto-flip point labels to avoid line collision#2

DominicBurkart wants to merge 2 commits intoclaude/add-xychart-point-labels-NYGcCDominicBurkart/mermaid:claude/add-xychart-point-labels-NYGcCfrom

claude/fix-label-line-collision-HNiTaDominicBurkart/mermaid:claude/fix-label-line-collision-HNiTaCopy head branch name to clipboard