feat(pos): wire history reprint to redirect to receipt page

public/pos/history.html

@@ -220,6 +220,9 @@ async function load(){
       method: METHOD_LABELS[s.payment_method] || 'Cash',
       dt: new Date(s.created),
     }));
+    // Cache for reprint() — needs both the PosSale and its PosSaleItems
+    // to reconstruct the sessionStorage shape that receipt.html expects.
+    cachedRows = rows;
     const grandTotal = rows.reduce((sum,r)=>sum+r.total,0);
     document.getElementById('kpiCount').textContent = sales.length;
     document.getElementById('kpiTotal').textContent = fmt(grandTotal);
@@ -244,8 +247,61 @@ async function load(){
   }
 }
 
+// Cached after each load() — lets reprint() look up the full PosSale +
+// PosSaleItems for a clicked row without re-fetching. The list is the
+// only source of truth for "what's on screen", so this stays in sync
+// whenever the user picks a different day.
+let cachedRows = [];
+
+// Reprint = hop to receipt.html with the sale stashed in
+// sessionStorage. The receipt page already handles loading from
+// sessionStorage and has the full Bluetooth / Network print logic
+// (including the epos-print.js network path added 2026-09-03), so we
+// just translate the API shape into the till-rendered shape and let
+// the existing code drive the printer.
 window.reprint = function(orderId){
-  alert('Reprint: slip ' + orderId + '. (Use the browser print dialog to re-print.)');
+  const row = cachedRows.find(r => r.s.id === orderId);
+  if(!row){
+    alert('Sale not loaded — try again after the list finishes loading.');
+    return;
+  }
+  const s = row.s;
+  const sessionSale = {
+    localId: s.client_ref || s.id,
+    createdAt: s.created,
+    payment: s.payment_method,
+    cashGiven: s.cash_given || 0,
+    change: s.change_given || 0,
+    gross: s.gross_total,
+    discount: {
+      kind: s.discount_kind || 'none',
+      input: s.discount_input || 0,
+      amount: s.discount_amount || 0,
+    },
+    sub: s.subtotal,
+    vat: s.vat,
+    total: s.total,
+    items: row.items.map(it => ({
+      sku: it.sku,
+      description: it.description,
+      unit: 'ea',
+      cost_price: it.unit_cost,
+      selling_price: it.unit_price,
+      edited: false,
+      qty: it.qty,
+      product_id: it.stock_item,
+    })),
+    // The API returns the customer as a relation id only (no name
+    // expansion in the sales list). Pass null so receipt.html's
+    // `if (s.customer)` guard skips the line — better than printing
+    // "Customer: undefined". If we need the name, the user can add
+    // a /api/v1/pos/sales/:id endpoint that expands it.
+    customer: null,
+    synced: true,
+    serverRef: s.id,
+  };
+  try{ sessionStorage.setItem('pos.lastSale', JSON.stringify(sessionSale)); }catch(_){}
+  setTimeout(() => { location.href = 'receipt.html'; }, 80);
 };
 
 paintDays(); load();