* [FEATURE] Add auth query param to /api/verify (#1353)
When `/api/verify` is called with `?auth=basic`, use the standard
Authorization header instead of Proxy-Authorization.
* [FIX] Better basic auth error reporting
* [FIX] Return 401 when using basic auth instead of redirecting
* [TESTS] Add tests for auth=basic query param
* [DOCS] Mention auth=basic argument and provide nginx example
* docs: add/adjust basic auth query arg docs for proxies
Co-authored-by: Amir Zarrinkafsh <nightah@me.com>