Add Authority Advisory AI and API Lifecycle Configuration

- Introduced AuthorityAdvisoryAiOptions and related classes for managing advisory AI configurations, including remote inference options and tenant-specific settings.
- Added AuthorityApiLifecycleOptions to control API lifecycle settings, including legacy OAuth endpoint configurations.
- Implemented validation and normalization methods for both advisory AI and API lifecycle options to ensure proper configuration.
- Created AuthorityNotificationsOptions and its related classes for managing notification settings, including ack tokens, webhooks, and escalation options.
- Developed IssuerDirectoryClient and related models for interacting with the issuer directory service, including caching mechanisms and HTTP client configurations.
- Added support for dependency injection through ServiceCollectionExtensions for the Issuer Directory Client.
- Updated project file to include necessary package references for the new Issuer Directory Client library.

docs/notifications/digests.md

@@ -63,7 +63,7 @@ Digest state lives in Mongo (`digests` collection) and mirrors the schema descri
 | Endpoint | Description | Notes |
 |----------|-------------|-------|
 | `POST /digests` | Issues administrative commands (e.g., force flush, reopen) for a specific action/window. | Request body specifies the command target; requires `notify.admin`. |
-| `GET /digests/{actionKey}` | Returns the currently open window (if any) for the referenced action. | Supports operators/CLI inspecting pending digests; requires `notify.read`. |
+| `GET /digests/{actionKey}` | Returns the currently open window (if any) for the referenced action. | Supports operators/CLI inspecting pending digests; requires `notify.viewer`. |
 | `DELETE /digests/{actionKey}` | Drops the open window without notifying (emergency stop). | Emits an audit record; use sparingly. |
 
 All routes honour the tenant header and reuse the standard Notify rate limits.