Add per-meal calorie cap (1000 kcal) + kcal/protein display

- SKILL.md RATIONAL PORTIONS: add ~1000 kcal/meal cap; trim starch/cheese/halloumi/lentil
  (not protein) if over; use scripts/calc_meal.py to check
- scripts/calc_meal.py: estimate protein/kcal/fibre/satfat for a meal's items, flag
  over_kcal (>1000) + per-item max_per_meal breaches (unit-aware); gates daily sends
- scripts/verify_portions.py: now also flags KCAL CAP violations via calc_meal
- references/calories.md: per-portion kcal/macro estimate table (source of truth)
- references/email-template.md + meal-history.md: show Est. kcal + Protein per card/entry
- daily cron prompt: compute + record kcal/protein_g on each entry, show kcal in email,
  enforce 1000 kcal cap before send (pushed via cronjob update)

references/meal-history.md

@@ -11,7 +11,9 @@ job must record them into `meal-history.json` (same skill dir) so the user can l
   "weekday": "Thursday",
   "meal": "lunch" | "dinner",
   "name": "Human-readable meal name",
-  "items": [ { "name": "Name as in inventory.json", "qty": 1, "unit": "count" }, ... ]
+  "items": [ { "name": "Name as in inventory.json", "qty": 1, "unit": "count" }, ... ],
+  "kcal": 720,
+  "protein_g": 64
 }
 ```