mathem-cli

# Mathem CLI 1. Run `npx --yes mathem-cli --help`. Continue when help works. 2. Extract foods, quantities, budget, dietary constraints, quality criteria, and substitutions. For quality-sensitive food such as meat, shortlist products unless origin, cut, or production method makes the choice unambiguous. 3. Search with `npx --yes mathem-cli search "<query>" --limit <count>` and inspect candidates with `npx --yes mathem-cli product <id>`. Compare published ingredients, allergens, nutrition, origin, freshness, availability, and unit price. 4. Run `npx --yes mathem-cli list`. If authentication is required, run `npx --yes mathem-cli login` and let the user complete the Chrome flow. Continue when `list` returns JSON. 5. Mutate one item at a time with `npx --yes mathem-cli add <id> [quantity]`, `npx --yes mathem-cli update <quantity> <id>`, or `npx --yes mathem-cli delete <id>`. Verify each returned cart; after an uncertain result, run `list` before retrying. 6. Run `npx --yes mathem-cli list` and report the final items, quantities, totals, quality trade-offs, and unknown fields. Rules: - Prefer product IDs. - Treat `null` as unknown and zero as measured zero. - Treat private API failures as contract drift; preserve the last verified cart state. - Stop at the verified cart. Checkout, payment, delivery slots, and order confirmation stay with the user.