Add /login/status/{aid} endpoint

[2byrds]

Add /login/status/{aid} endpoint indicates if the LAST user login status.
Note the the verifier has this authorization endpoint, which is a start but more information should be provided back through the api:

• https://github.com/GLEIF-IT/vlei-verifier/blob/main/src/verifier/core/verifying.py#L204
• https://github.com/GLEIF-IT/vlei-verifier/blob/c28678ab97a77e7ff5fc7c3c7f1b704dee4bb4c7/README.md?plain=1#L33

This call requires signed headers from the same ID because no other user should be able to see the login status for this AID.

The status should indicate the LAST login status such as:

• If the user tries to make the call without signed headers, the error message should say they need to sign headers.
• If the last login was a failure then the signed headers won't validate, so the error message should indicate that the user needs to login with a valid ECR credential.
• If the user has submitted a login request with a valid ECR credential and calls this endpoint with valid signed headers then the response should contain a status with details about the LAST login, including the JSON form of the CESR, see Supply the 'raw' JSON version of the CESR, as part of the login success response vlei-verifier#35

There should be tests for all these scenarios for this endpoint, as well as multiple calls and a mixture of calls.