fix: Invoice print layout - hide app shell, fix padding

Print CSS:
- Hide WooNooW app nav, header, submenu, bottom nav
- Set print-a4 to absolute positioning for clean print
- Added 15mm padding for print
- Hidden min-height for screen container

Invoice Component:
- Removed inline minHeight to prevent empty second page
- Added max-w-3xl and p-8 for screen display
- Added print:max-w-none print:p-0 for print mode

admin-spa/src/routes/Orders/Invoice.tsx

@@ -87,16 +87,8 @@ export default function Invoice() {
             </div>
 
             {/* Invoice content */}
-            <div className="py-8 print:py-0">
-                <div
-                    className="print-a4 bg-white shadow-lg print:shadow-none mx-auto"
-                    style={{
-                        width: '210mm',
-                        minHeight: '297mm',
-                        padding: '20mm',
-                        boxSizing: 'border-box'
-                    }}
-                >
+            <div className="py-8 print:py-0 print:bg-white">
+                <div className="print-a4 bg-white shadow-lg print:shadow-none mx-auto max-w-3xl p-8 print:max-w-none print:p-0">
                     {/* Invoice Header */}
                     <div className="flex items-start justify-between mb-8 pb-6 border-b-2 border-gray-200">
                         <div>
@@ -214,6 +206,6 @@ export default function Invoice() {
                     </div>
                 </div>
             </div>
-        </div>
+        </div >
     );
 }