feat(commons): add DTOs

Moving the DTOs to commons so frontend and backend use the same types.
Also introducing zod for validation.

Co-authored-by: Erik Michelson <github@erik.michelson.eu>
Signed-off-by: Erik Michelson <github@erik.michelson.eu>
Signed-off-by: Philip Molares <philip.molares@udo.edu>

backend/src/auth/provider-type.enum.ts

@@ -1,12 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2024 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-
-export enum ProviderType {
-  GUEST = 'guest',
-  LOCAL = 'local',
-  LDAP = 'ldap',
-  OIDC = 'oidc',
-}

backend/src/config/guest_access.enum.ts

@@ -1,27 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-
-export enum GuestAccess {
-  DENY = 'deny',
-  READ = 'read',
-  WRITE = 'write',
-  CREATE = 'create',
-}
-
-export function getGuestAccessOrdinal(guestAccess: GuestAccess): number {
-  switch (guestAccess) {
-    case GuestAccess.DENY:
-      return 0;
-    case GuestAccess.READ:
-      return 1;
-    case GuestAccess.WRITE:
-      return 2;
-    case GuestAccess.CREATE:
-      return 3;
-    default:
-      throw Error('Unknown permission');
-  }
-}