Composant React pour inclure un Document PAIR

**Tension**
Il faudrait pouvoir inclure des Documents PAIR (ou des parties de Documents) dans des pages React.

**Proposition**
Un composant `Document` qui prend comme props:
- `id`: l'URI du Document
- `truncate`: si true, n'affiche qu'un extrait du document
- `showFooter`: si true, affiche en bas un lien pour éditer le document, évent. la date

No file or test is named in the issue. Start by locating the existing React component entry points and how PAIR Document URIs are loaded; then define the component around the listed props. Done means a Document component can render a full or truncated document and optionally show an edit link and date in its footer.

Written by the indexing model from the issue text.