perf: skip bunding Mermaid ZenUML

[aloisklink]

📑 Summary

Instead of bundling the @mermaid-js/mermaid-zenuml package ourselves, we can let the user install their own version of it.

📏 Design Decisions

This lowers the size of the dist/index.html file by about 1.3 MB:

Before

$ npx vite build
vite v4.5.5 building for production...
✓ 656 modules transformed.
dist/index.html  5,627.39 kB │ gzip: 2,451.54 kB
✓ built in 9.67s

After

$ npx vite build
vite v4.5.5 building for production...
✓ 638 modules transformed.
dist/index.html  4,340.56 kB │ gzip: 2,124.28 kB
✓ built in 6.63s

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added unit/e2e tests (if appropriate)
• 🔖 targeted master branch