Compute gram weights for ingredients

Compute gram weights for ingredient items — convert quantities to grams using portion data and standard measurement tables.

③ of 8 | Next: ⑤ updateRecipeIngredients Stateless — no recipe needed yet.

Use this to answer: "how many grams is 2 cups of flour?", "convert 3 eggs to grams", "get gram weight for these ingredients", "what does 1 pinch of saffron weigh?"

Called when ② searchUsIngredients returns null gram_weight and resolve_options points here. Accepts a batch of (ingredient_id, quantity, unit) items and returns gram weights.

When no portion match exists, returns resolve_options guiding the caller to either re-call with allow_estimation: true (system estimate) or ask the user for quantity_grams directly.

curl -X POST "https://loading/ingredients/us/conversions/compute" \  -H "Content-Type: application/json" \  -d '{    "items": [      {        "ingredient_id": "string",        "quantity": "2",        "unit": "cup"      }    ]  }'

{}

{
  "detail": [
    {
      "loc": [
        "string"
      ],
      "msg": "string",
      "type": "string",
      "input": null,
      "ctx": {}
    }
  ]
}