Extract nutrition and diet information from this medical document. Return a JSON array or null.

Each entry:
- type: "observation", "restriction", "tolerance"
- value: (empty)
- summary: brief description, e.g. "Tolerating solid foods well"
- timestamp: "YYYY-MM-DD" if date mentioned
- data: {"description": "...", "details": "..."}

Document:
{{MARKDOWN}}