API keys are now only visible when first created. After that, only the first four characters are stored in the database for identification, along with an sha256 hash of the full key. This makes key usage easier to audit, and ensures attackers would not have access to the live site in the event of a database leak.
This makes the merge lower risk, because we have some time to revert if needed. Once the change is confirmed to be working, we will add a second commit to drop the `key` column.
- Allow revoking keys without deleting them
- Auto-revoke keys after a period of no use (default 6 months)
- Allow multiple keys per user
- Allow attaching a description to each key, for easier auditing
- Log changes to keys in the staff action log
- Move all key management to one place, and improve the UI
