v4.1.0: DMS email documents, category-specific Nachweis linking, version system

- Save cover email body as DMS document with new 'email' context type
- Show email body separately from attachments in email detail view
- Add per-category DMS document assignment in quarterly confirmation
  (Studiennachweis, Einkommenssituation, Vermögenssituation)
- Add VERSION file and context processor for automatic version display
- Add MCP server, agent system, import/export, and new migrations
- Update compose files and production environment template

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

env-production.template

@@ -68,6 +68,14 @@ GRAMPS_USERNAME=admin@vhtv-stiftung.de
 GRAMPS_PASSWORD=your_grampsweb_admin_password_here
 GRAMPS_API_TOKEN=your_gramps_api_token_if_needed
 
+# OLLAMA KONFIGURATION (AI Agent)
+# Standard-Modell für 8 GB RAM Server (ohne GPU):
+#   qwen2.5:3b (~2 GB) — Empfohlen (bester Kompromiss)
+#   phi3:mini  (~2.3 GB) — Alternative
+#   gemma2:2b  (~1.5 GB) — Schnellste Option
+#   llama3.2:3b (~2 GB) — Solide Basis
+OLLAMA_DEFAULT_MODEL=qwen2.5:3b
+
 # =============================================================================
 # GENERATE SECRET KEYS:
 # =============================================================================