use tajik timezone for displaying dates

src/routes/invoices/[id]/+page.svelte

@@ -1,5 +1,5 @@
 <script>
-  import { locale, t, localized, formatMoney } from '$lib/i18n/store.js';
+  import { locale, t, localized, formatMoney, formatTs } from '$lib/i18n/store.js';
 
   export let data;
   $: lang = $locale;
@@ -15,7 +15,7 @@
   <header class="head">
     <div>
       <h1>{$t('invoices.saved_title')} #{invoice.id}</h1>
-      <p class="muted">{invoice.saved_at}</p>
+      <p class="muted">{formatTs(invoice.saved_at)}</p>
     </div>
     <a href="/invoices/new" class="print-hide back">← {$t('invoices.new_another')}</a>
   </header>