Save this content to: .cursor/rules/30-frontend-ts-vite-pentatrion.mdc

Work only on the requested module or stylesheet.

Prefer:
- strict TypeScript typing; English JSDoc on exported APIs
- the current build: one ES-module library entry `src/Resources/assets/src/index.ts` → `src/Resources/public/milkdown-editor.js`
  (+ `milkdown-editor.css`, `chunks/`, `katex/`), produced by `make assets`
- heavy features (CodeMirror, KaTeX, Mermaid, collaboration, top bar) stay behind dynamic `import()`; check `make bundle-size`
- DOM built with `createElement` / `textContent` (no `innerHTML` with user data, no inline handlers, no eval)
- the Markdown dialect is shared with the PHP renderer: change both and their tests together
- keep CSP compatibility: styles through the stylesheet or CSSOM, nonces for injected style elements
- running `make test-ts` (Vitest with coverage) and `make lint-ts` after a change

Do not inspect or edit generated build output under `src/Resources/public/`.
The bundle does not use Pentatrion Vite Bundle; do not add `vite_entry_*` tags to bundle templates.
Do not use Crepe's list-item, image-block, block-edit, AI or emoji features (a11y, remote images, CSP).