Feature: OIDC & social authentication (#5190)

---------

Co-authored-by: Moritz Pflanzer <moritz@chickadee-engineering.com>
Co-authored-by: shamoon <4887959+shamoon@users.noreply.github.com>

src-ui/src/app/services/django-messages.service.ts

@@ -0,0 +1,27 @@
+import { Injectable } from '@angular/core'
+
+// see https://docs.djangoproject.com/en/5.0/ref/contrib/messages/#message-tags
+export enum DjangoMessageLevel {
+  DEBUG = 'debug',
+  INFO = 'info',
+  SUCCESS = 'success',
+  WARNING = 'warning',
+  ERROR = 'error',
+}
+
+export interface DjangoMessage {
+  level: DjangoMessageLevel
+  message: string
+}
+
+@Injectable({
+  providedIn: 'root',
+})
+export class DjangoMessagesService {
+  constructor() {}
+
+  get(): DjangoMessage[] {
+    // These are embedded in the HTML as raw JS, the service is for convenience
+    return window['DJANGO_MESSAGES'] ?? []
+  }
+}