feat: add Steuertags concept to separate workflow from content tags

- New steuertag_ids setting to mark tags as workflow-only (not editable)
- DocumentEditModal shows only content tags (non-Steuertags) as editable chips
- Backend preserves Steuertags when saving document tag changes
- ManuellBearbeitenPage renders content tag chips under document title
- New Steuertags settings tab with multi-select and color preview

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

paperless-frontend/src/components/DocumentEditModal.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useState, useCallback } from 'react';
-import { Modal, Form, Select, DatePicker, Input, Spin, message, Row, Col, Button, Space, Divider } from 'antd';
+import { Modal, Form, Select, DatePicker, Input, Spin, message, Row, Col, Button, Space, Divider, Tag } from 'antd';
 import { PlusOutlined, EyeOutlined, SearchOutlined } from '@ant-design/icons';
 import dayjs from 'dayjs';
 import { posteingangApi } from '../api/posteingang';
@@ -7,7 +7,7 @@ import type { DocumentRequirement, PosteingangDocument, Kontonummer } from '../a
 import { clientsApi } from '../api/inbox';
 import type { Client } from '../api/inbox';
 import { paperlessApi } from '../api/paperless';
-import type { PaperlessDocType, PaperlessCorrespondent } from '../api/paperless';
+import type { PaperlessDocType, PaperlessCorrespondent, PaperlessTag } from '../api/paperless';
 import { getEnv } from '../utils/env';
 import { AuthIframe, openAuthUrl } from '../utils/auth-resource';
 import DocumentSearchModal from './DocumentSearchModal';
@@ -35,6 +35,11 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
   const [correspondents, setCorrespondents] = useState<PaperlessCorrespondent[]>([]);
   const [requirements, setRequirements] = useState<DocumentRequirement[]>([]);
 
+  // Tags: alle Tags + als Steuertags markierte IDs; bearbeitbar sind nur Inhaltstags
+  const [allTags, setAllTags] = useState<PaperlessTag[]>([]);
+  const [steuertagIds, setSteuertagIds] = useState<number[]>([]);
+  const contentTags = allTags.filter(t => !steuertagIds.includes(t.id));
+
   const [kontonummerMissing, setKontonummerMissing] = useState<{ correspondentId: number, nummer: string } | null>(null);
   const [docTitles, setDocTitles] = useState<Record<number, string>>({});
   const [searchModalOpen, setSearchModalOpen] = useState<{ field: string, reqId: number } | null>(null);
@@ -140,6 +145,14 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
     }
   }, [document, form, open]);
 
+  // Tags getrennt setzen: nur Inhaltstags (Steuertags werden nicht angezeigt/bearbeitet)
+  useEffect(() => {
+    if (open && document) {
+        const contentTagIds = (document.tags || []).filter(id => !steuertagIds.includes(id));
+        form.setFieldValue('tags', contentTagIds);
+    }
+  }, [document, open, steuertagIds, form]);
+
   const ensureCorrespondentInList = async (correspondentId: number | null | undefined) => {
     if (!correspondentId) return;
     
@@ -178,14 +191,18 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
   const loadInitialData = async () => {
     setLoading(true);
     try {
-      const [clientsData, docTypesData, correspondentsData] = await Promise.all([
+      const [clientsData, docTypesData, correspondentsData, tagsData, steuertagData] = await Promise.all([
         clientsApi.getMyClients(),
         paperlessApi.getDocumentTypes(),
-        paperlessApi.getCorrespondents()
+        paperlessApi.getCorrespondents(),
+        paperlessApi.getTags(),
+        paperlessApi.getSteuertagIds(),
       ]);
       setClients(clientsData);
       setDocumentTypes(docTypesData);
       setCorrespondents(correspondentsData);
+      setAllTags(tagsData);
+      setSteuertagIds(steuertagData);
       
       // If document is already there, ensure its correspondent is in the list
       if (document?.correspondent) {
@@ -258,6 +275,7 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
         correspondent: values.correspondent,
         title: values.title,
         date: values.belegdatum ? values.belegdatum.format('YYYY-MM-DD') : null,
+        tags: values.tags || [],
         customFields: customFieldsObj,
     };
 
@@ -373,6 +391,36 @@ export default function DocumentEditModal({ documentId, document, open, onClose,
                             <DatePicker style={{ width: '100%' }} format="DD.MM.YYYY" />
                         </Form.Item>
 
+                        <Form.Item name="tags" label="Tags">
+                            <Select
+                                mode="multiple"
+                                allowClear
+                                showSearch
+                                optionFilterProp="label"
+                                placeholder="Tags auswählen"
+                                options={contentTags.map(t => ({ value: t.id, label: t.name }))}
+                                tagRender={({ value, closable, onClose }) => {
+                                    const tag = allTags.find(t => t.id === value);
+                                    return (
+                                        <Tag
+                                            color={tag?.color}
+                                            style={{ color: tag?.text_color, marginInlineEnd: 4 }}
+                                            closable={closable}
+                                            onClose={onClose}
+                                        >
+                                            {tag?.name ?? value}
+                                        </Tag>
+                                    );
+                                }}
+                                optionRender={(opt) => {
+                                    const tag = contentTags.find(t => t.id === opt.value);
+                                    return tag ? (
+                                        <Tag color={tag.color} style={{ color: tag.text_color }}>{tag.name}</Tag>
+                                    ) : opt.label;
+                                }}
+                            />
+                        </Form.Item>
+
                         {/* Rendering dynamic requirements based on DocumentType */}
                         {requirements.map(req => {
                             if (req.feldId === '2' || (req.isCustomField && req.customFieldIndex === 9)) {