feat(accounting): move Treuhänder export onto the Tax page

The standalone 'Treuhänder export' tab duplicated the Tax page's period/
currency filters over the same data. Fold the collective-journal export into
the Tax page as a third export action (target-tool format picker: generic /
Banana / bexio), beside Export CSV/PDF, with a link to its Chart-of-accounts
config. Removes the Accounting sub-nav 'export' tab (old /export route now
redirects to the Tax page); keeps Chart of accounts as its own setup tab.
Deletes the now-orphaned LedgerExportPage.

Build + JSON parse green.

frontend/src/App.tsx

@@ -70,7 +70,6 @@ import { AccountingLayout, AccountingIndex } from './components/admin/Accounting
 import { AccountingInboxPage } from './pages/admin/accounting/AccountingInboxPage';
 import { ExpensesLedgerPage } from './pages/admin/accounting/ExpensesLedgerPage';
 import { ChartOfAccountsPage } from './pages/admin/accounting/ChartOfAccountsPage';
-import { LedgerExportPage } from './pages/admin/accounting/LedgerExportPage';
 import { RequireFeature } from './components/admin/RequireFeature';
 import { PageErrorBoundary, OfflineIndicator, SkipLink, DynamicFavicon, RobotsMetaTags, CMSContentBlock, Loading } from './components/common';
 import { MaintenanceWrapper } from './components/MaintenanceWrapper';
@@ -288,7 +287,9 @@ function App() {
                           </Route>
                           <Route element={<RequireFeature flag="taxReport" />}>
                             <Route path="tax-report" element={<TaxReportPage />} />
-                            <Route path="export" element={<LedgerExportPage />} />
+                            {/* Treuhänder export moved onto the Tax page; keep
+                                the old path working for bookmarks. */}
+                            <Route path="export" element={<Navigate to="/admin/accounting/tax-report" replace />} />
                           </Route>
                           {/* Chart of accounts + VAT codes (Layer A) — gated by
                               the accounting master flag alongside the section. */}

frontend/src/components/admin/AccountingLayout.tsx

@@ -9,7 +9,7 @@
 import React from 'react';
 import { NavLink, Outlet, Navigate, useLocation, useNavigate } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
-import { Landmark, Calculator, Inbox, Wallet, BookOpen, FileSpreadsheet } from 'lucide-react';
+import { Landmark, Calculator, Inbox, Wallet, BookOpen } from 'lucide-react';
 import type { LucideIcon } from 'lucide-react';
 import { useFeatureFlags, type FeatureKey } from '../../contexts/FeatureFlagsContext';
 
@@ -45,18 +45,13 @@ export const AccountingLayout: React.FC = () => {
     },
     {
       key: 'tax-report',
+      // The Treuhänder export now lives ON the Tax page (same period/currency
+      // filters, same data) instead of a separate sub-tab — see TaxReportPage.
       to: '/admin/accounting/tax-report',
       label: t('accounting.subnav.taxReport', 'Tax'),
       icon: Calculator,
       featureFlag: 'taxReport',
     },
-    {
-      key: 'export',
-      to: '/admin/accounting/export',
-      label: t('accounting.subnav.export', 'Treuhänder export'),
-      icon: FileSpreadsheet,
-      featureFlag: 'taxReport',
-    },
     {
       key: 'ledger',
       to: '/admin/accounting/ledger',

frontend/src/i18n/locales/de.json

@@ -3937,6 +3937,9 @@
       "currency": "Währung"
     },
     "exportPdf": "PDF exportieren",
+    "ledgerExport": "Treuhänder-Export",
+    "ledgerExportHint": "Doppelte Buchung für Ihren Treuhänder, abgebildet über Ihren Kontenplan.",
+    "ledgerExportConfigure": "Einrichten →",
     "exportCsv": "CSV exportieren",
     "exportFailed": "Export fehlgeschlagen. Bitte erneut versuchen.",
     "errorTitle": "Steuerliste konnte nicht geladen werden",

frontend/src/i18n/locales/en.json

@@ -3937,6 +3937,9 @@
       "currency": "Currency"
     },
     "exportPdf": "Export PDF",
+    "ledgerExport": "Treuhänder export",
+    "ledgerExportHint": "Double-entry journal for your accountant, mapped via your Chart of accounts.",
+    "ledgerExportConfigure": "Configure →",
     "exportCsv": "Export CSV",
     "exportFailed": "Export failed. Please try again.",
     "errorTitle": "Could not load tax report",

frontend/src/pages/admin/accounting/LedgerExportPage.tsx

@@ -1,126 +0,0 @@
-/**
- * Accounting → Treuhänder export (Layer A).
- *
- * Picks a period + currency + target tool, then downloads the collective
- * journal (accrual Buchungssätze) as CSV for import into the Treuhänder's
- * double-entry software. Output is a guideline — disclaimer on the page.
- */
-import React, { useMemo, useState } from 'react';
-import { useTranslation } from 'react-i18next';
-import { toast } from 'react-toastify';
-import { FileSpreadsheet, Download, AlertCircle } from 'lucide-react';
-import { Button, Card, CardContent, LocalizedDateInput } from '../../../components/common';
-import { ledgerService, type ExportFormat } from '../../../services/ledger.service';
-
-const selectCls = 'w-full rounded-md border border-neutral-300 dark:border-neutral-600 bg-white dark:bg-neutral-800 px-3 py-2 text-sm text-neutral-900 dark:text-neutral-100 focus:outline-none focus:ring-2 focus:ring-primary-500';
-const labelCls = 'block text-xs font-medium text-neutral-700 dark:text-neutral-300 mb-1';
-
-type PeriodPreset = 'thisYear' | 'lastYear' | 'thisQuarter' | 'lastQuarter' | 'custom';
-const FORMATS: ExportFormat[] = ['generic', 'banana', 'bexio'];
-
-function periodForPreset(preset: PeriodPreset, today = new Date()): { from: string; to: string } {
-  const y = today.getFullYear();
-  const pad = (n: number) => String(n).padStart(2, '0');
-  if (preset === 'thisYear') return { from: `${y}-01-01`, to: `${y}-12-31` };
-  if (preset === 'lastYear') return { from: `${y - 1}-01-01`, to: `${y - 1}-12-31` };
-  const quarter = Math.floor(today.getMonth() / 3);
-  if (preset === 'thisQuarter') {
-    const sm = quarter * 3; const em = sm + 2;
-    return { from: `${y}-${pad(sm + 1)}-01`, to: `${y}-${pad(em + 1)}-${pad(new Date(y, em + 1, 0).getDate())}` };
-  }
-  let qy = y; let q = quarter - 1; if (q < 0) { q = 3; qy = y - 1; }
-  const sm = q * 3; const em = sm + 2;
-  return { from: `${qy}-${pad(sm + 1)}-01`, to: `${qy}-${pad(em + 1)}-${pad(new Date(qy, em + 1, 0).getDate())}` };
-}
-
-function triggerDownload(url: string, filename: string) {
-  const a = document.createElement('a');
-  a.href = url; a.download = filename; a.style.display = 'none';
-  document.body.appendChild(a); a.click(); document.body.removeChild(a);
-  setTimeout(() => URL.revokeObjectURL(url), 4000);
-}
-
-export const LedgerExportPage: React.FC = () => {
-  const { t } = useTranslation();
-  const [preset, setPreset] = useState<PeriodPreset>('thisYear');
-  const initial = useMemo(() => periodForPreset('thisYear'), []);
-  const [from, setFrom] = useState(initial.from);
-  const [to, setTo] = useState(initial.to);
-  const [currency, setCurrency] = useState('CHF');
-  const [format, setFormat] = useState<ExportFormat>('generic');
-  const [busy, setBusy] = useState(false);
-
-  const onPreset = (next: PeriodPreset) => {
-    setPreset(next);
-    if (next !== 'custom') { const p = periodForPreset(next); setFrom(p.from); setTo(p.to); }
-  };
-
-  const handleExport = async () => {
-    setBusy(true);
-    try {
-      const { url, filename } = await ledgerService.downloadExportUrl({ from, to, currency, format });
-      triggerDownload(url, filename);
-    } catch (e: any) {
-      toast.error(e?.response?.data?.error || e.message || t('ledger.export.failed', 'Export failed.'));
-    } finally { setBusy(false); }
-  };
-
-  return (
-    <Card padding="md">
-      <CardContent className="p-0">
-        <div className="flex items-start gap-3 mb-4">
-          <div className="w-10 h-10 rounded-lg bg-accent-soft text-on-accent-soft flex items-center justify-center flex-shrink-0">
-            <FileSpreadsheet className="w-5 h-5" />
-          </div>
-          <div>
-            <h1 className="text-lg font-semibold text-neutral-900 dark:text-neutral-100">{t('ledger.export.title', 'Treuhänder export')}</h1>
-            <p className="text-sm text-neutral-600 dark:text-neutral-400 mt-0.5">{t('ledger.export.intro', 'Download the collective journal (revenue + costs as accrual postings with account and VAT codes) for import into your Treuhänder’s accounting software.')}</p>
-          </div>
-        </div>
-
-        <div className="space-y-3 max-w-md">
-          <div>
-            <label className={labelCls}>{t('taxReport.filters.period', 'Period')}</label>
-            <select value={preset} onChange={(e) => onPreset(e.target.value as PeriodPreset)} className={selectCls}>
-              <option value="thisYear">{t('taxReport.filters.thisYear', 'This year')}</option>
-              <option value="lastYear">{t('taxReport.filters.lastYear', 'Last year')}</option>
-              <option value="thisQuarter">{t('taxReport.filters.thisQuarter', 'This quarter')}</option>
-              <option value="lastQuarter">{t('taxReport.filters.lastQuarter', 'Last quarter')}</option>
-              <option value="custom">{t('taxReport.filters.custom', 'Custom range')}</option>
-            </select>
-          </div>
-          <div className="grid grid-cols-2 gap-3">
-            <div><label className={labelCls}>{t('taxReport.filters.from', 'From')}</label><LocalizedDateInput value={from} onChange={(iso) => { setFrom(iso); setPreset('custom'); }} /></div>
-            <div><label className={labelCls}>{t('taxReport.filters.to', 'To')}</label><LocalizedDateInput value={to} onChange={(iso) => { setTo(iso); setPreset('custom'); }} /></div>
-          </div>
-          <div className="grid grid-cols-2 gap-3">
-            <div>
-              <label className={labelCls}>{t('taxReport.filters.currency', 'Currency')}</label>
-              <select value={currency} onChange={(e) => setCurrency(e.target.value)} className={selectCls}>
-                <option value="CHF">CHF</option><option value="EUR">EUR</option><option value="USD">USD</option><option value="GBP">GBP</option>
-              </select>
-            </div>
-            <div>
-              <label className={labelCls}>{t('ledger.export.format', 'Target tool')}</label>
-              <select value={format} onChange={(e) => setFormat(e.target.value as ExportFormat)} className={selectCls}>
-                {FORMATS.map((f) => <option key={f} value={f}>{t(`ledger.export.format_${f}`, f)}</option>)}
-              </select>
-            </div>
-          </div>
-          <div className="flex justify-end pt-1">
-            <Button onClick={handleExport} disabled={busy || !from || !to} isLoading={busy} leftIcon={<Download className="w-4 h-4" />}>
-              {t('ledger.export.download', 'Download CSV')}
-            </Button>
-          </div>
-        </div>
-
-        <p className="flex items-start gap-2 mt-5 text-xs text-neutral-500 dark:text-neutral-400">
-          <AlertCircle className="w-4 h-4 flex-shrink-0 mt-0.5" />
-          <span>{t('ledger.export.disclaimer', 'Accrual basis only (document dates) — payments/bank movements are not included. Account + VAT codes follow your Chart-of-accounts mapping. Always review the import with your Treuhänder before filing.')}</span>
-        </p>
-      </CardContent>
-    </Card>
-  );
-};
-
-export default LedgerExportPage;

frontend/src/pages/admin/clients/TaxReportPage.tsx

@@ -17,7 +17,8 @@
 import React, { useMemo, useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useQuery } from '@tanstack/react-query';
-import { Calculator, Download, FileDown, AlertCircle } from 'lucide-react';
+import { Calculator, Download, FileDown, FileSpreadsheet, AlertCircle } from 'lucide-react';
+import { Link } from 'react-router-dom';
 import { Button, Card, Loading, LocalizedDateInput } from '../../../components/common';
 
 // Lightweight native select styled to match Input — the common barrel
@@ -26,9 +27,12 @@ import { Button, Card, Loading, LocalizedDateInput } from '../../../components/c
 const selectClassName =
   'w-full rounded-md border border-neutral-300 dark:border-neutral-600 bg-white dark:bg-neutral-800 px-3 py-2 text-sm text-neutral-900 dark:text-neutral-100 focus:outline-none focus:ring-2 focus:ring-primary-500';
 import { taxReportService, type TaxReportParams } from '../../../services/taxReport.service';
+import { ledgerService, type ExportFormat } from '../../../services/ledger.service';
 import { useLocalizedDate } from '../../../hooks/useLocalizedDate';
 import { toast } from 'react-toastify';
 
+const LEDGER_FORMATS: ExportFormat[] = ['generic', 'banana', 'bexio'];
+
 type PeriodPreset = 'thisYear' | 'lastYear' | 'thisQuarter' | 'lastQuarter' | 'custom';
 
 function isoDate(d: Date): string {
@@ -95,7 +99,10 @@ export const TaxReportPage: React.FC = () => {
   const [from, setFrom] = useState(initialPeriod.from);
   const [to,   setTo]   = useState(initialPeriod.to);
   const [currency, setCurrency] = useState<string>('CHF');
-  const [isExporting, setIsExporting] = useState<'pdf' | 'csv' | null>(null);
+  const [isExporting, setIsExporting] = useState<'pdf' | 'csv' | 'ledger' | null>(null);
+  // Treuhänder (collective-journal) export — same period/currency as the
+  // report; target tool picks the import format (generic / Banana / bexio).
+  const [ledgerFormat, setLedgerFormat] = useState<ExportFormat>('generic');
   // Unified-ledger sort (#5). Defaults to date ascending — matches the
   // server-side order so the first paint is stable.
   const [sort, setSort] = useState<{ key: string; dir: 'asc' | 'desc' }>({ key: 'date', dir: 'asc' });
@@ -136,6 +143,22 @@ export const TaxReportPage: React.FC = () => {
     }
   };
 
+  // Treuhänder collective-journal export (double-entry postings with account +
+  // VAT codes) — reuses the page's period/currency, adds the target-tool format.
+  const handleLedgerExport = async () => {
+    setIsExporting('ledger');
+    try {
+      const { url, filename } = await ledgerService.downloadExportUrl({ from, to, currency, format: ledgerFormat });
+      triggerBrowserDownload(url, filename);
+    } catch (err: any) {
+      toast.error(err?.response?.data?.error || t('taxReport.exportFailed', 'Export failed. Please try again.'));
+      // eslint-disable-next-line no-console
+      console.error(err);
+    } finally {
+      setIsExporting(null);
+    }
+  };
+
   // Per maintainer: every CH/LI/DE/AT-based business writes 1'000.00
   // regardless of document language, so we default to de-CH (the only
   // Intl locale producing apostrophe thousands). Non-DACH operators
@@ -271,7 +294,8 @@ export const TaxReportPage: React.FC = () => {
               </select>
             </div>
 
-            <div className="flex flex-wrap items-center justify-end gap-2 pt-1">
+            <div className="space-y-2 pt-1">
+              <div className="flex flex-wrap items-center justify-end gap-2">
                 <Button
                   variant="outline"
                   onClick={() => handleExport('csv')}
@@ -291,6 +315,38 @@ export const TaxReportPage: React.FC = () => {
                   {t('taxReport.exportPdf', 'Export PDF')}
                 </Button>
               </div>
+
+              {/* Treuhänder collective-journal export — moved here from its own
+                  tab; reuses the same period/currency. Format = target tool. */}
+              <div className="flex flex-wrap items-center justify-end gap-2">
+                <select
+                  value={ledgerFormat}
+                  onChange={(e) => setLedgerFormat(e.target.value as ExportFormat)}
+                  disabled={exportsDisabled}
+                  aria-label={t('ledger.export.format', 'Target tool') as string}
+                  className={`${selectClassName} w-auto`}
+                >
+                  {LEDGER_FORMATS.map((f) => (
+                    <option key={f} value={f}>{t(`ledger.export.format_${f}`, f)}</option>
+                  ))}
+                </select>
+                <Button
+                  variant="outline"
+                  onClick={handleLedgerExport}
+                  disabled={exportsDisabled}
+                  isLoading={isExporting === 'ledger'}
+                  leftIcon={<FileSpreadsheet className="w-4 h-4" />}
+                >
+                  {t('taxReport.ledgerExport', 'Treuhänder export')}
+                </Button>
+              </div>
+              <p className="text-[11px] text-neutral-400 dark:text-neutral-500 text-right">
+                {t('taxReport.ledgerExportHint', 'Double-entry journal for your accountant, mapped via your Chart of accounts.')}{' '}
+                <Link to="/admin/accounting/ledger" className="underline hover:text-neutral-600 dark:hover:text-neutral-300">
+                  {t('taxReport.ledgerExportConfigure', 'Configure →')}
+                </Link>
+              </p>
+            </div>
           </div>
         </Card>