Adds the storage model and authorization contracts needed for multiple
environment API keys. Credentials are represented by hashed values,
revocation and expiration state, and persisted effective scopes.
The built-in authorization fallback exposes full-access policy
preparation, while optional authorization extensions can supply
additional presets and task-aware scope generation. This change does not
create, display, or authenticate additional keys.
Chris Arderne
a81ad4949c