Add Vorlagen editor, upload portal, onboarding, and participant import command

- Dokument-Vorlagen-Editor: create/edit/reset document templates (admin)
- Upload-Portal: public portal for Nachweis uploads via token
- Onboarding: invite Destinatäre via email with multi-step wizard
- Bestätigungsschreiben: preview and send confirmation letters
- Email settings: SMTP configuration UI
- Management command: import_veranstaltung_teilnehmer for bulk participant import

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/core/settings.py

@@ -118,8 +118,11 @@ MEDIA_URL = "/media/"
 MEDIA_ROOT = BASE_DIR / "media"
 
 # Celery
-CELERY_BROKER_URL = os.getenv("REDIS_URL", "redis://redis:6379/0")
-CELERY_RESULT_BACKEND = os.getenv("REDIS_URL", "redis://redis:6379/0")
+CELERY_BROKER_URL = os.getenv("CELERY_REDIS_URL", os.getenv("REDIS_URL", "redis://redis:6379/2"))
+CELERY_RESULT_BACKEND = os.getenv("CELERY_REDIS_URL", os.getenv("REDIS_URL", "redis://redis:6379/2"))
+CELERY_TASK_SERIALIZER = "json"
+CELERY_RESULT_SERIALIZER = "json"
+CELERY_ACCEPT_CONTENT = ["json"]
 
 # Celery Beat – periodische Tasks
 from celery.schedules import crontab  # noqa: E402
@@ -130,6 +133,11 @@ CELERY_BEAT_SCHEDULE = {
         "task": "stiftung.tasks.poll_emails",
         "schedule": crontab(minute="*/15"),
     },
+    # Täglich um 08:00 Uhr: Ablaufende Upload-Tokens prüfen und Erinnerungen versenden
+    "check-ablaufende-tokens": {
+        "task": "stiftung.tasks.check_ablaufende_tokens",
+        "schedule": crontab(hour="8", minute="0"),
+    },
 }
 
 # IMAP-Konfiguration für E-Mail-Eingang (Destinatäre)
@@ -141,6 +149,16 @@ IMAP_PASSWORD = os.getenv("IMAP_PASSWORD", "")
 IMAP_FOLDER = os.getenv("IMAP_FOLDER", "INBOX")
 IMAP_USE_SSL = os.getenv("IMAP_USE_SSL", "true").lower() == "true"
 
+# SMTP-Konfiguration für E-Mail-Ausgang (Nachweis-Aufforderungen, Einladungen)
+# Pflichtfelder: EMAIL_HOST_USER, EMAIL_HOST_PASSWORD
+EMAIL_HOST = os.getenv("EMAIL_HOST", "smtp.ionos.de")
+EMAIL_PORT = int(os.getenv("EMAIL_PORT") or "465")
+EMAIL_USE_SSL = os.getenv("EMAIL_USE_SSL", "true").lower() == "true"
+EMAIL_HOST_USER = os.getenv("EMAIL_HOST_USER", "")
+EMAIL_HOST_PASSWORD = os.getenv("EMAIL_HOST_PASSWORD", "")
+DEFAULT_FROM_EMAIL = os.getenv("DEFAULT_FROM_EMAIL", "stiftung@vhtv-stiftung.de")
+EMAIL_SUBJECT_PREFIX = "[vHTV-Stiftung] "
+
 
 # Authentication
 LOGIN_URL = "/login/"