Core V3: a 401 caused by an extra Authorization header

If a Yotpo API V3 request has an Authorization: Bearer header, the API checks that header instead of X-Yotpo-Token and returns 401 {"message":"Bad token; invalid JSON"}, even when the token is valid. Remove the Authorization header and send the token in X-Yotpo-Token only.

This shows up most with the docs MCP, which passes your MCP client's headers on to the API. The 401 response on every V3 endpoint now documents this case, and the MCP guide has a warning. Generate access token and the Loyalty API aren't affected.