feat(drafts): show Koncept for null numbers in lists + fix filtered empty-state

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

src/admin/pages/Invoices.tsx

@@ -49,6 +49,7 @@ import {
   statusLabel,
   statusColor,
   statusOptions,
+  documentNumberLabel,
 } from "../lib/documentStatus";
 
 const ReceivedInvoices = lazy(() => import("./ReceivedInvoices"));
@@ -517,7 +518,7 @@ export default function Invoices() {
             "&:hover": { textDecoration: "underline" },
           }}
         >
-          {inv.invoice_number}
+          {documentNumberLabel(inv.invoice_number)}
         </Box>
       ),
     },

src/admin/pages/IssuedOrders.tsx

@@ -33,6 +33,7 @@ import {
   statusLabel,
   statusColor,
   statusOptions,
+  documentNumberLabel,
 } from "../lib/documentStatus";
 
 const API_BASE = "/api/admin";
@@ -206,7 +207,7 @@ export default function IssuedOrders({ month, year }: IssuedOrdersProps) {
             "&:hover": { textDecoration: "underline" },
           }}
         >
-          {o.po_number || "—"}
+          {documentNumberLabel(o.po_number)}
         </Box>
       ),
     },

src/admin/pages/Offers.tsx

@@ -46,6 +46,7 @@ import {
   statusLabel,
   statusColor,
   statusOptions,
+  documentNumberLabel,
 } from "../lib/documentStatus";
 
 const API_BASE = "/api/admin";
@@ -543,6 +544,10 @@ export default function Offers() {
     label: f.label,
   }));
 
+  // Search/status filter is active → an empty list means "nothing matches"
+  // (no create CTA); a genuinely empty list keeps the create-CTA empty state.
+  const isFiltered = !!debouncedSearch || !!statusFilter;
+
   const columns: DataColumn<Quotation>[] = [
     {
       key: "quotation_number",
@@ -559,7 +564,7 @@ export default function Offers() {
             "&:hover": { textDecoration: "underline" },
           }}
         >
-          {q.quotation_number}
+          {documentNumberLabel(q.quotation_number)}
         </Box>
       ),
     },
@@ -851,8 +856,11 @@ export default function Offers() {
           sortDir={order}
           onSort={handleSort}
           empty={
-            debouncedSearch ? (
-              <EmptyState title="Žádné nabídky odpovídající hledání." />
+            isFiltered ? (
+              <EmptyState
+                title="Žádné nabídky neodpovídají filtru"
+                description="Zkuste změnit filtr nebo hledaný výraz."
+              />
             ) : (
               <EmptyState
                 title="Zatím nejsou žádné nabídky."