- Add user_agent to remote_storage_authorizations and rs_authorization_codes
- Capture the browser's user agent at consent, carry it on the authorization
code, and store it on the authorization when the code is exchanged
- Store it directly for the implicit flow too
With the reuse shortcut gone, each authorization is already a distinct
per-device token; this adds the metadata needed to label and display them.
Part of #254
raucao
583bd882db