Add back Auth provider types

packages/celest/lib/celest.dart

@@ -3,13 +3,21 @@ library celest;
 
 export 'package:celest_core/celest_core.dart';
 
+/// Auth
+export 'src/auth/auth.dart';
+export 'src/auth/auth_provider.dart';
+
 /// Config
 export 'src/config/env.dart';
 
 /// Core
 export 'src/core/cloud_widget.dart';
+export 'src/core/context.dart';
 export 'src/core/project.dart';
 
 /// Functions
 export 'src/functions/cloud_api.dart';
 export 'src/functions/cloud_function.dart';
+
+/// Grants
+export 'src/grants/grants.dart';

packages/celest/lib/src/auth/auth_provider.dart

@@ -2,15 +2,15 @@
 /// An authentication provider which can be used to sign in to Celest.
 ///
 /// Currently, Celest supports the following authentication methods:
-/// - [AuthProvider.google] Sign in with Google
+/// - [AuthProvider.email] Email sign-in with OTP codes.
 /// {@endtemplate}
 sealed class AuthProvider {
   const AuthProvider();
 
-  /// A provider which enables Sign in with Google.
-  const factory AuthProvider.google() = _GoogleAuthProvider;
+  /// A provider which enables email sign-in with OTP codes.
+  const factory AuthProvider.email() = _EmailAuthProvider;
 }
 
-final class _GoogleAuthProvider extends AuthProvider {
-  const _GoogleAuthProvider();
+final class _EmailAuthProvider extends AuthProvider {
+  const _EmailAuthProvider();
 }

packages/celest/lib/src/core/context.dart

@@ -0,0 +1,30 @@
+import 'package:celest/celest.dart';
+
+/// The context of a [CloudFunction] invocation.
+abstract final class Context {
+  const Context._();
+
+  /// A context reference to the [User] invoking a [CloudFunction].
+  ///
+  /// ## Example
+  ///
+  /// To inject a user into an `@authenticated` function:
+  ///
+  /// ```dart
+  /// @authenticated
+  /// Future<void> sayHello({
+  ///  @Context.user() required User user,
+  /// }) async {
+  ///  print('Hello, ${user.displayName}!');
+  /// }
+  /// ```
+  const factory Context.user() = _ContextKey.user;
+}
+
+final class _ContextKey extends Context {
+  const _ContextKey._(this.key) : super._();
+
+  const _ContextKey.user() : this._('user');
+
+  final String key;
+}

packages/celest/lib/src/core/project.dart

@@ -11,14 +11,8 @@ class Project implements CloudWidget {
   /// {@macro celest.core.project}
   const Project({
     required this.name,
-    this.logoUrl,
   });
 
   /// The name of the project as its identified in your Celest backend.
   final String name;
-
-  /// The hosted URL of your project's logo.
-  ///
-  /// This is used by widgets like [Auth] to craft a custom login page.
-  final String? logoUrl;
 }

packages/celest/lib/src/grants/grants.dart

@@ -0,0 +1,40 @@
+import 'package:celest/src/core/entity.dart';
+
+/// A grant which provides access to all authenticated users.
+///
+/// ## Example
+///
+/// ```dart
+/// import 'package:celest/celest.dart';
+///
+/// @authenticated
+/// Future<void> sayHello() async {
+///   print('User is authenticated!');
+/// }
+/// ```
+const authenticated = _Authenticated();
+
+final class _Role implements Entity {
+  const _Role({
+    required this.name,
+  });
+
+  static const _Role authenticated = _Role(name: r'$authenticated');
+
+  final String name;
+}
+
+/// An assignment which grants a set of permissions to a specific group of
+/// [Entity]s.
+final class _Grant {
+  const _Grant({
+    required this.to,
+  });
+
+  /// The group of [Entity] which are granted access.
+  final List<Entity> to;
+}
+
+final class _Authenticated extends _Grant {
+  const _Authenticated() : super(to: const [_Role.authenticated]);
+}