feat(ui): invoice notes use RichEditor (sanitized render + PDF), matching offers/orders

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/pages/InvoiceDetail.tsx

@@ -23,6 +23,7 @@ import { useApiMutation } from "../lib/queries/mutations";
 import { useAlert } from "../context/AlertContext";
 import { useAuth } from "../context/AuthContext";
 import Forbidden from "../components/Forbidden";
+import RichEditor from "../components/RichEditor";
 import {
   DndContext,
   closestCenter,
@@ -2158,13 +2159,9 @@ export default function InvoiceDetail() {
           <Typography variant="subtitle2" sx={{ mb: 2, fontWeight: 600 }}>
             Veřejné poznámky na faktuře
           </Typography>
-          <TextField
-            multiline
-            minRows={4}
+          <RichEditor
             value={form.notes}
-            onChange={(e) =>
-              setForm((prev) => ({ ...prev, notes: e.target.value }))
-            }
+            onChange={(val) => setForm((prev) => ({ ...prev, notes: val }))}
             placeholder="Poznámky zobrazené na faktuře..."
           />
         </Card>