debug: Add debug markers to verify ProductsController is running
Added debug markers:
1. _debug field in response with timestamp
2. X-WooNooW-Version header
3. Improved variation attribute retrieval
Issue: API returns different structure than code produces
Response has: id, name, price (only 9 fields)
Code returns: id, name, type, status, price, etc (15+ fields)
This suggests:
- Response is cached somewhere
- Different controller handling request
- Middleware transforming response
Debug steps:
1. Check response for _debug field
2. Check response headers for X-WooNooW-Version
3. If missing, endpoint not using our code
4. Check wp-content/debug.log for error messages
bc733ab2a6