chore(cloud_auth): Make Authorizer a class (#283)

So that it can be implemented for fakes.

Author: dnys1

services/celest_cloud_auth/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.2.1-wip
+
+- chore: Make `Authorizer` a class
+
 ## 0.2.0
 
 - refactor(cloud_auth)!: Consolidate session logic (#273)

services/celest_cloud_auth/lib/src/authorization/authorizer.dart

@@ -6,11 +6,13 @@ import 'package:celest_core/celest_core.dart';
 import 'package:logging/logging.dart';
 import 'package:meta/meta.dart';
 
-extension type Authorizer._(AuthDatabase _db) implements Object {
-  Authorizer({required AuthDatabase db}) : this._(db);
+class Authorizer {
+  Authorizer({required AuthDatabase db}) : _db = db;
 
   static final Logger _logger = Logger('Celest.Authorizer');
 
+  final AuthDatabase _db;
+
   Future<void> expectAuthorized({
     Component? principal,
     Component? resource,

services/celest_cloud_auth/pubspec.yaml

@@ -1,6 +1,6 @@
 name: celest_cloud_auth
 description: A Dart-native authentication and authorization service built on Celest, Cedar, and SQLite.
-version: 0.2.0
+version: 0.2.1-wip
 homepage: https://celest.dev
 repository: https://github.com/celest-dev/celest/tree/main/services/celest_cloud_auth