Generalize email system with invoice workflow and Stiftungsgeschichte category

- Rename DestinataerEmailEingang → EmailEingang with category support
  (destinataer, rechnung, land_pacht, stiftungsgeschichte, allgemein)
- Add invoice capture workflow: create Verwaltungskosten from email,
  link DMS documents as invoice attachments, track payment status
- Add Stiftungsgeschichte email category with auto-detection patterns
  (Ahnenforschung, Genealogie, Chronik, etc.) and DMS integration
- Update poll_emails task with category detection and DMS context mapping
- Show available history documents in Geschichte editor sidebar
- Consolidate DMS views, remove legacy dokument templates
- Update all detail/form templates for DMS document linking
- Add deploy.sh script and streamline compose.yml

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

app/templates/stiftung/dms/upload.html

@@ -18,6 +18,8 @@
 
         <form method="post" enctype="multipart/form-data" id="upload-form">
             {% csrf_token %}
+            {% if initial.foerderung_id %}<input type="hidden" name="foerderung_id" value="{{ initial.foerderung_id }}">{% endif %}
+            {% if initial.verpachtung_id %}<input type="hidden" name="verpachtung_id" value="{{ initial.verpachtung_id }}">{% endif %}
 
             <!-- Drag & Drop Zone -->
             <div class="card shadow mb-4">