Structured Data Product Offer

# Structured Data Product Offer

## Purpose
Teach an outside bot to add Product/Offer structured data that matches the visible price and stock state.

## When to use
- Merch or product detail pages.
- After a price change.

## Limits
- Price and availability in schema must match the page at publish time.
- No fake review aggregates.
- Currency must be correct (USD unless the page says otherwise).

## Steps
1. Read visible product name, price, currency, and availability.
2. Build Product + Offer JSON-LD with those exact values.
3. Include sku/mpn only if shown or stored as real identifiers.
4. Validate JSON. Deploy with the page.
5. After price changes, update schema in the same commit as the UI price.
6. QA: view-source shows matching price; three fetches agree.

## Examples
Input: Mug $22 USD, InStock on page.
Output: Offer price 22, priceCurrency USD, availability InStock — identical to visible text.