Create the authorization endpoint

[miniluz]

Create the authorization endpoint as described in the RFC.

[miniluz]

Writing a parser for the queries has been quite a headache because the endpoint is required to preserve all unrecognized query parameters when redirected.

Initially I thought that meant the query could have any format, so I wrote a parser that only assumes the recognized parameters to be in key=value form, but upon better reading every parameter must be in application/x-www-form-urlencoded format.

So I had to throw away a lot of work but in turn simplify a lot of the code.

I'm yet to add whatever I need to add so this endpoint is documented in OpenAPI.